The change in gene frequency in a population due to migration of gametes or individuals (ANIMAL MIGRATION) across population barriers. In contrast, in GENETIC DRIFT the cause of gene frequency changes are not a result of population or gamete movement.
The discipline studying genetic composition of populations and effects of factors such as GENETIC SELECTION, population size, MUTATION, migration, and GENETIC DRIFT on the frequencies of various GENOTYPES and PHENOTYPES using a variety of GENETIC TECHNIQUES.
Genotypic differences observed among individuals in a population.
The splitting of an ancestral species into daughter species that coexist in time (King, Dictionary of Genetics, 6th ed). Causal factors may include geographic isolation, HABITAT geometry, migration, REPRODUCTIVE ISOLATION, random GENETIC DRIFT and MUTATION.
A variety of simple repeat sequences that are distributed throughout the GENOME. They are characterized by a short repeat unit of 2-8 basepairs that is repeated up to 100 times. They are also known as short tandem repeats (STRs).
The science dealing with the earth and its life, especially the description of land, sea, and air and the distribution of plant and animal life, including humanity and human industries with reference to the mutual relations of these elements. (From Webster, 3d ed)
The flow of BLOOD through or around an organ or region of the body.
A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.
The genetic process of crossbreeding between genetically dissimilar parents to produce a hybrid.
Double-stranded DNA of MITOCHONDRIA. In eukaryotes, the mitochondrial GENOME is circular and codes for ribosomal RNAs, transfer RNAs, and about 10 proteins.
Periodic movements of animals in response to seasonal changes or reproductive instinct. Hormonal changes are the trigger in at least some animals. Most migrations are made for reasons of climatic change, feeding, or breeding.
Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.
The biological objects that contain genetic information and that are involved in transmitting genetically encoded traits from one organism to another.
A field of study concerned with the principles and processes governing the geographic distributions of genealogical lineages, especially those within and among closely related species. (Avise, J.C., Phylogeography: The History and Formation of Species. Harvard University Press, 2000)
Mechanisms that prevent different populations from exchanging genes (GENE FLOW), resulting in or maintaining GENETIC SPECIATION. It can either prevent mating to take place or ensure that any offspring produced is either inviable or sterile, thereby preventing further REPRODUCTION.
The relationships of groups of organisms as reflected by their genetic makeup.
The fluctuation of the ALLELE FREQUENCY from one generation to the next.
The pattern of any process, or the interrelationship of phenomena, which affects growth or change within a population.
The detection of RESTRICTION FRAGMENT LENGTH POLYMORPHISMS by selective PCR amplification of restriction fragments derived from genomic DNA followed by electrophoretic analysis of the amplified restriction fragments.
The genetic constitution of individuals with respect to one member of a pair of allelic genes, or sets of genes that are closely linked and tend to be inherited together such as those of the MAJOR HISTOCOMPATIBILITY COMPLEX.
The fertilizing element of plants that contains the male GAMETOPHYTES.
The total genetic information possessed by the reproductive members of a POPULATION of sexually reproducing organisms.
Theoretical representations that simulate the behavior or activity of genetic processes or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.
A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)
The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.
In evolutionary theory, overlapping geographic distribution of diverging species. In sympatric GENETIC SPECIATION, genetic diversion occurs without geographic separation.
Differential and non-random reproduction of different genotypes, operating to alter the gene frequencies within a population.
The total process by which organisms produce offspring. (Stedman, 25th ed)
The process of cumulative change over successive generations through which organisms acquire their distinguishing morphological and physiological characteristics.
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
The transfer of POLLEN grains (male gametes) to the plant ovule (female gamete).
The geographical area of Africa comprising ALGERIA; EGYPT; LIBYA; MOROCCO; and TUNISIA. It includes also the vast deserts and oases of the Sahara. It is often referred to as North Africa, French-speaking Africa, or the Maghreb. (From Webster's New Geographical Dictionary, 1988, p856)
A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.
Rhythmic, intermittent propagation of a fluid through a BLOOD VESSEL or piping system, in contrast to constant, smooth propagation, which produces laminar flow.
An animal or plant species in danger of extinction. Causes can include human activity, changing climate, or change in predator/prey ratios.
The proportion of one particular in the total of all ALLELES for one genetic locus in a breeding POPULATION.
Slender-bodies diurnal insects having large, broad wings often strikingly colored and patterned.
Number of individuals in a population relative to space.
The various physical methods which include wind, insects, animals, tension, and water, by which a plant scatters its seeds away from the parent plant.
The mating of plants or non-human animals which are closely related genetically.
Deoxyribonucleic acid that makes up the genetic material of plants.
Woody, usually tall, perennial higher plants (Angiosperms, Gymnosperms, and some Pterophyta) having usually a main stem and numerous branches.
A plant family of the order Lecythidales, subclass Dilleniidae, class Magnoliopsida.
A plant genus of the family FAGACEAE that is a source of TANNINS. Do not confuse with Holly (ILEX).
A phenotypically recognizable genetic trait which can be used to identify a genetic locus, a linkage group, or a recombination event.
Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.
A theorem in probability theory named for Thomas Bayes (1702-1761). In epidemiology, it is used to obtain the probability of disease in a group of people with some characteristic on the basis of the overall rate of that disease and of the likelihood of that characteristic in healthy and diseased individuals. The most familiar application is in clinical decision analysis where it is used for estimating the probability of a particular diagnosis given the appearance of some symptoms or test result.
A plant genus in the family PINACEAE, order Pinales, class Pinopsida, division Coniferophyta. They are evergreen trees mainly in temperate climates.
Specific regions that are mapped within a GENOME. Genetic loci are usually identified with a shorthand notation that indicates the chromosome number and the position of a specific band along the P or Q arm of the chromosome where they are found. For example the locus 6p21 is found within band 21 of the P-arm of CHROMOSOME 6. Many well known genetic loci are also known by common names that are associated with a genetic function or HEREDITARY DISEASE.
The human male sex chromosome, being the differential sex chromosome carried by half the male gametes and none of the female gametes in humans.
The encapsulated embryos of flowering plants. They are used as is or for animal feed because of the high content of concentrated nutrients like starches, proteins, and fats. Rapeseed, cottonseed, and sunflower seed are also produced for the oils (fats) they yield.
The regular and simultaneous occurrence in a single interbreeding population of two or more discontinuous genotypes. The concept includes differences in genotypes ranging in size from a single nucleotide site (POLYMORPHISM, SINGLE NUCLEOTIDE) to large nucleotide sequences visible at a chromosomal level.
Statistical interpretation and description of a population with reference to distribution, composition, or structure.
Large members of the FALCONIFORMES order of birds, family Accipitridae, most especially the genera Aquila, Haliaeetus, Harpia, and Circaetus. They are characterized by their powerful talons, which carry long, curved, pointed claws and by their opposable hindtoe.
A plant genus of the family OLEACEAE. Members contain secoiridoid glucosides.
Periodic movement of human settlement from one geographical location to another.
Deoxyribonucleic acid that makes up the genetic material of CHLOROPLASTS.
A plant genus of the family RANUNCULACEAE that contains protoanemonin, anemonin, and ranunculin.
The MEDITERRANEAN SEA, the MEDITERRANEAN ISLANDS, and the countries bordering on the sea collectively.
Cultivated plants or agricultural produce such as grain, vegetables, or fruit. (From American Heritage Dictionary, 1982)
The process of leaving one's country to establish residence in a foreign country.
Systems of agriculture which adhere to nationally regulated standards that restrict the use of pesticides, non-organic fertilizers, genetic engineering, growth hormones, irradiation, antibiotics, and non-organic ANIMAL FEED.
The branch of science concerned with the interrelationship of organisms and their ENVIRONMENT, especially as manifested by natural cycles and rhythms, community development and structure, interactions between different kinds of organisms, geographic distributions, and population alterations. (Webster's, 3d ed)
The geographical area of Africa comprising BENIN; BURKINA FASO; COTE D'IVOIRE; GAMBIA; GHANA; GUINEA; GUINEA-BISSAU; LIBERIA; MALI; MAURITANIA; NIGER; NIGERIA; SENEGAL; SIERRA LEONE; and TOGO.
The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.
The total number of individuals inhabiting a particular region or area.
The pygmy chimpanzee, a species of the genus Pan, family HOMINIDAE. Its common name is Bonobo, which was once considered a separate genus by some; others considered it a subspecies of PAN TROGLODYTES. Its range is confined to the forests of the central Zaire basin. Despite its name, it is often of equal size to P. troglodytes.
The geographical area of Africa comprising CAMEROON; CENTRAL AFRICAN REPUBLIC; CHAD; CONGO; EQUATORIAL GUINEA; GABON; and DEMOCRATIC REPUBLIC OF THE CONGO.
A widely distributed order of perching BIRDS, including more than half of all bird species.
A plant genus of the family Phrymaceae. Members contain 6-geranylflavanones and mimulone.
Functions constructed from a statistical model and a set of observed data which give the probability of that data for various values of the unknown model parameters. Those parameter values that maximize the probability are the maximum likelihood estimates of the parameters.
A plant genus of the family ROSACEAE.
Geological formations consisting of underground enclosures with access from the surface.
The male sex chromosome, being the differential sex chromosome carried by half the male gametes and none of the female gametes in humans and in some other male-heterogametic species in which the homologue of the X chromosome has been retained.
A process by which animals in various forms and stages of development are physically distributed through time and space.
The mahogany plant family of the order Sapindales, subclass Rosidae, class Magnoliopsida.
A vertical distance measured from a known level on the surface of a planet or other celestial body.
The circulation of blood through the BLOOD VESSELS of the BRAIN.
The motion of air relative to the earth's surface.
Tracts of land completely surrounded by water.
A plant family of the order Campanulales, subclass Asteridae, class Magnoliopsida
Diminished or failed response of PLANTS to HERBICIDES.
Changes in biological features that help an organism cope with its ENVIRONMENT. These changes include physiological (ADAPTATION, PHYSIOLOGICAL), phenotypic and genetic changes.
The circulation of blood through the CORONARY VESSELS of the HEART.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
A genus of BROWN ALGAE in the family Fucaceae. It is found in temperate, marine intertidal areas along rocky coasts and is a source of ALGINATES. Some species of Fucus are referred to as KELP.
The study of the deformation and flow of matter, usually liquids or fluids, and of the plastic flow of solids. The concept covers consistency, dilatancy, liquefaction, resistance to flow, shearing, thixotrophy, and VISCOSITY.
A plant species cultivated for the seed used as animal feed and as a source of canola cooking oil.
Cytochromes of the b group that have alpha-band absorption of 563-564 nm. They occur as subunits in MITOCHONDRIAL ELECTRON TRANSPORT COMPLEX III.
The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.
A region, north-central Asia, largely in Russia. It extends from the Ural Mountains to the Pacific Ocean and from the Arctic Ocean to central Kazakhstan and the borders of China and Mongolia.
Sexual activities of animals.
A plant family of the order Lamiales. It is characterized by simple leaves in opposite pairs, cystoliths (enlarged cells containing crystals of calcium carbonate), and bilaterally symmetrical and bisexual flowers that are usually crowded together. The common name for Ruellia of wild petunia is easily confused with PETUNIA.
A plant genus of the family BRASSICACEAE. Member species are ornamentals grown for their numerous small white, yellow, pink, or purplish flowers.
A plant genus of the family POACEAE.
The external elements and conditions which surround, influence, and affect the life and development of an organism or population.
A republic in southern Africa, south of ANGOLA and west of BOTSWANA. Its capital is Windhoek.
The protection, preservation, restoration, and rational use of all resources in the total environment.
Nonrandom association of linked genes. This is the tendency of the alleles of two separate but already linked loci to be found together more frequently than would be expected by chance alone.
A genus of mosquitoes (CULICIDAE) that are known vectors of MALARIA.
A set of statistical methods used to group variables or observations into strongly inter-related subgroups. In epidemiology, it may be used to analyze a closely grouped series of events or cases of disease or other health-related phenomenon with well-defined distribution patterns in relation to time or place or both.
Mathematical procedure that transforms a number of possibly correlated variables into a smaller number of uncorrelated variables called principal components.
A plant genus of the family FABACEAE that contains julibroside (triterpenoid saponins).
The cactus plant family of the order Caryophyllales, subclass Caryophyllidae, class Magnoliopsida. Cacti are succulent perennial plants well adapted to dry regions.
PLANTS, or their progeny, whose GENOME has been altered by GENETIC ENGINEERING.
A class in the phylum MOLLUSCA comprised of SNAILS and slugs. The former have coiled external shells and the latter usually lack shells.
The region of southwest Asia and northeastern Africa usually considered as extending from Libya on the west to Afghanistan on the east. (From Webster's New Geographical Dictionary, 1988)
The largest of the continents. It was known to the Romans more specifically as what we know today as Asia Minor. The name comes from at least two possible sources: from the Assyrian asu (to rise) or from the Sanskrit usa (dawn), both with reference to its being the land of the rising sun, i.e., eastern as opposed to Europe, to the west. (From Webster's New Geographical Dictionary, 1988, p82 & Room, Brewer's Dictionary of Names, 1992, p34)
Deliberate breeding of two different individuals that results in offspring that carry part of the genetic material of each parent. The parent organisms must be genetically compatible and may be from different varieties or closely related species.
The continuous visual field seen by a subject through space and time.
A plant genus of the family FAGACEAE.
The period of history before 500 of the common era.
A plant genus in the family PINACEAE, order Pinales, class Pinopsida, division Coniferophyta. Balm of Gilead is a common name more often referring to POPULUS and sometimes to COMMIPHORA.

Speciation and gene flow between snails of opposite chirality. (1/998)

Left-right asymmetry in snails is intriguing because individuals of opposite chirality are either unable to mate or can only mate with difficulty, so could be reproductively isolated from each other. We have therefore investigated chiral evolution in the Japanese land snail genus Euhadra to understand whether changes in chirality have promoted speciation. In particular, we aimed to understand the effect of the maternal inheritance of chirality on reproductive isolation and gene flow. We found that the mitochondrial DNA phylogeny of Euhadra is consistent with a single, relatively ancient evolution of sinistral species and suggests either recent "single-gene speciation" or gene flow between chiral morphs that are unable to mate. To clarify the conditions under which new chiral morphs might evolve and whether single-gene speciation can occur, we developed a mathematical model that is relevant to any maternal-effect gene. The model shows that reproductive character displacement can promote the evolution of new chiral morphs, tending to counteract the positive frequency-dependent selection that would otherwise drive the more common chiral morph to fixation. This therefore suggests a general mechanism as to how chiral variation arises in snails. In populations that contain both chiral morphs, two different situations are then possible. In the first, gene flow is substantial between morphs even without interchiral mating, because of the maternal inheritance of chirality. In the second, reproductive isolation is possible but unstable, and will also lead to gene flow if intrachiral matings occasionally produce offspring with the opposite chirality. Together, the results imply that speciation by chiral reversal is only meaningful in the context of a complex biogeographical process, and so must usually involve other factors. In order to understand the roles of reproductive character displacement and gene flow in the chiral evolution of Euhadra, it will be necessary to investigate populations in which both chiral morphs coexist.  (+info)

Macrogeographic population structure of the tsetse fly, Glossina pallidipes (Diptera: Glossinidae). (2/998)

Tsetse flies are confined to sub-Saharan Africa where they occupy discontinuous habitats. In anticipation of area-wide control programmes, estimates of gene flow among tsetse populations are necessary. Genetic diversities were partitioned at eight microsatellite loci and five mitochondrial loci in 21 Glossina pallidipes Austin populations. At microsatellite loci, Nei's unbiased gene diversity averaged over loci was 0.659 and the total number of alleles was 214, only four of which were shared among all populations. The mean number of alleles per locus was 26.8. Random mating was observed within but not among populations (fixation index FST=0.18) and 81% of the genetic variance was within populations. Thirty-nine mitochondrial variants were detected. Mitochondrial diversities in populations varied from 0 to 0.85 and averaged 0.42, and FST=0.51. High levels of genetic differentiation were characteristic, extending even to subpopulations separated by tens and hundreds of kilometres, and indicating low rates of gene flow.  (+info)

Gene flow and hybridisation in a mixed oak forest (Quercus pyrenaica Willd. and Quercus petraea (Matts.) Liebl.) in central Spain. (3/998)

Oaks are long-standing models for the study of gene flow and hybridisation. Temperate (Quercus petraea) and sub-Mediterranean (Quercus pyrenaica) oaks coexist in central Spain, showing remarkable differences in population size and structure. Q. petraea has a scattered distribution in central Spain, where it is at one of the southernmost limits of its range, and forms low-density stands; in contrast, Q. pyrenaica is widespread in the region. We selected a mixed population of the two species ( approximately 13 ha, 176 adults and 96 saplings) to compare the patterns of gene flow within each species and the extent of introgression between them. Using five nuclear microsatellite markers, we performed a parentage analysis and found considerable immigration from outside the stand ( approximately 38% for Q. petraea and approximately 34% for Q. pyrenaica), and estimated average seed-dispersal distances of 42 and 14 m for Q. petraea and Q. pyrenaica, respectively. Introgression between species was also estimated using our microsatellite battery. First, we developed a multivariate discriminant approach and, second, we compared our results with a widely used clustering method (STRUCTURE). Both analyses were consistent with a low level of introgression between Q. petraea and Q. pyrenaica. Indeed, only 15 adult trees, approximately 8.5%, were identified as putative hybrids when both methods of analysis were combined. Hybrids may be most common in contact zones due merely to physical proximity.  (+info)

Effect of gene flow on spatial genetic structure in the riparian canopy tree Cercidiphyllum japonicum revealed by microsatellite analysis. (4/998)

Few studies have analyzed pollen and seed movements at local scale, and genetic differentiation among populations covering the geographic distribution range of a species. We carried out such a study on Cercidiphyllum japonicum; a dioecious broad-leaved tree of cool-temperate riparian forest in Japan. We made direct measurement of pollen and seed movements in a site, genetic structure at the local scale, and genetic differentiation between populations covering the Japanese Archipelago. Parentage analysis of seedlings within a 20-ha study site indicated that at least 28.8% of seedlings were fertilized by pollen from trees outside the study site. The average pollination distance within the study site was 129 m, with a maximum of 666 m. The genotypes of 30% of seedlings were incompatible with those of the nearest female tree, and the maximum seed dispersal distance within the study site was over 300 m. Thus, long-distance gene dispersal is common in this species. The correlation between genetic relatedness and spatial distance among adult trees within the population was not significant, indicating an absence of fine-scale genetic structure perhaps caused by high levels of pollen flow and overlapping seed shadows. Six populations sampled throughout the distribution of C. japonicum in Japan showed significant isolation-by-distance but low levels of genetic differentiation (F(ST) = 0.043), also indicating long-distance gene flow in C. japonicum. Long-distance gene flow had a strong influence on the genetic structure at different spatial scales, and contributes to the maintenance of genetic diversity in C. japonicum.  (+info)

Evidence for a one-allele assortative mating locus. (5/998)

Theoretical models have shown that speciation with gene flow can occur readily via a "one-allele mechanism," where the spread of the same allele within both of two diverging species reduces their subsequent hybridization. Here we present direct genetic evidence for such an allele in Drosophila pseudoobscura. Alleles conferring high or low assortative mating in D. pseudoobscura produce the same effects when inserted into D. persimilis. This observation suggests that the type of genetic variation that is most conducive to controversial modes of speciation with gene flow, such as reinforcement or sympatric speciation, is present in nature.  (+info)

Genetic structure of Anopheles gambiae populations on islands in northwestern Lake Victoria, Uganda. (6/998)

BACKGROUND: Alternative means of malaria control are urgently needed. Evaluating the effectiveness of measures that involve genetic manipulation of vector populations will be facilitated by identifying small, genetically isolated vector populations. The study was designed to use variation in microsatellite markers to look at genetic structure across four Lake Victoria islands and two surrounding mainland populations and for evidence of any restriction to free gene flow. METHODS: Four Islands (from 20-50 km apart) and two surrounding mainland populations (96 km apart) were studied. Samples of indoor resting adult mosquitoes, collected over two consecutive years, were genotyped at microsatellite loci distributed broadly throughout the genome and analysed for genetic structure, effective migration (Nem) and effective population size (Ne). RESULTS: Ne estimates showed island populations to consist of smaller demes compared to the mainland ones. Most populations were significantly differentiated geographically, and from one year to the other. Average geographic pair-wise FST ranged from 0.014-0.105 and several pairs of populations had Ne m < 3. The loci showed broad heterogeneity at capturing or estimating population differences. CONCLUSION: These island populations are significantly genetically differentiated. Differences reoccurred over the study period, between the two mainland populations and between each other. This appears to be the product of their separation by water, dynamics of small populations and local adaptation. With further characterisation these islands could become possible sites for applying measures evaluating effectiveness of control by genetic manipulation.  (+info)

Phylogeographic history and gene flow among giant Galapagos tortoises on southern Isabela Island. (7/998)

Volcanic islands represent excellent models with which to study the effect of vicariance on colonization and dispersal, particularly when the evolution of genetic diversity mirrors the sequence of geological events that led to island formation. Phylogeographic inference, however, can be particularly challenging for recent dispersal events within islands, where the antagonistic effects of land bridge formation and vicariance can affect movements of organisms with limited dispersal ability. We investigated levels of genetic divergence and recovered signatures of dispersal events for 631 Galapagos giant tortoises across the volcanoes of Sierra Negra and Cerro Azul on the island of Isabela. These volcanoes are among the most recent formations in the Galapagos (<0.7 million years), and previous studies based on genetic and morphological data could not recover a consistent pattern of lineage sorting. We integrated nested clade analysis of mitochondrial DNA control region sequences, to infer historical patterns of colonization, and a novel Bayesian multilocus genotyping method for recovering evidence of recent migration across volcanoes using eleven microsatellite loci. These genetic studies illuminate taxonomic distinctions as well as provide guidance to possible repatriation programs aimed at countering the rapid population declines of these spectacular animals.  (+info)

Effective seed dispersal across a fragmented landscape. (8/998)

The role of seed dispersal in maintaining genetic connectivity among forest fragments has largely been ignored because gene flow by pollen is expected to predominate. By using genealogical reconstruction, we investigated gene flow after establishment of seeds in a wind-pollinated, wind-dispersed tree. Our data show that seed dispersal is the main vector of gene flow among remnants and that long-distance dispersal is common across a chronically fragmented landscape. The relative importance of seed-mediated gene flow may have been underemphasized in other fragmented systems, and diagnosing the response of forest trees to current anthropogenic disturbances requires the assessment of phenomena after establishment.  (+info)

Although historical gene flow in the tiger metapopulation of central India has mitigated the drift-induced subdivision and has been in a state of migration-drift equilibrium, contemporary gene flow has been reduced. A comparison of the spatial pattern of remnant forest patches and the pattern of contemporary gene flow further confirms that there is a drastic reduction in gene flow among those tiger reserve pairs (Kanha-Satpura, Pench-Melghat and Kanha-Melghat) that have lost forest connectivity. Gene flow has been maintained at the same scale between the remaining tiger reserve pairs owing to the existing functional corridor between them. These results support our hypothesis about genetic connectivity of the predefined TCLs owing to presence of functional corridors. Based on the significant gene flow between TCL pairs, we suggest consolidating these pairs into a genetically connected single metapopulation. We also advise reclassifying the tiger landscape taxonomy in the light of genetic ...
Interspecific gene flow is an important aspect in avian speciation [54]. Based on hybridization networks and D-statistics, calculated from genome-wide data, we found indications for high levels of interspecific gene flow between several goose species. D-statistics allowed us to confidently discriminate between incomplete lineage sorting and interspecific gene flow. The significant D-statistics varied from 0.07 to 0.17, which is slightly higher compared to analyses on recent radiations, such as Darwins Finches (0.004-0.092; [55]) and butterflies of the genera Heliconius (0.04; [56]) and Papilio (0.04; [57]). These values do fall within the range of studies on other hybridizing species, such as pigs (0.11-0.23; [58]), bears (0.04-0.46; [59, 60]) and Xiphophorus fish (0.03-0.56; [61]).. A significant D-statistic does not necessarily indicate introgression between the species from which the genomes are being compared. There might have been gene flow with an extinct (not sampled) population or the ...
Determining the frequency and genetic impact of hybridization during animal speciation remains a central and unresolved issue in evolutionary biology. If reproductive isolation is incomplete when nascent species come into contact, even moderate gene flow may result in population fusion. Thus, recurrent hybridization among animal species has traditionally been viewed as rare. Alternatively, genetic factors underlying speciation may continue to accumulate between divergent populations despite on-going gene flow, eventually leading to the evolution of complete reproductive isolation. Consistent with this second model (divergence with gene flow), several recent studies have shown that closely related taxa may retain differentiation despite high levels of cryptic hybridization and introgression. If divergence with gene flow is common, then hybridization may often be an important transient phase in animal speciation. Furthermore, in such cases, phylogeny estimation in such cases will be rendered ...
Effects of polyploidisation on gene flow between natural populations are little known. Central European diploid and tetraploid populations of Arabidopsis arenosa and A. lyrata are here used to study interspecific and interploidal gene flow, using a combination of nuclear and plastid markers. Ploidal levels were confirmed by flow cytometry. Network analyses clearly separated diploids according to species. Tetraploids and diploids were highly intermingled within species, and some tetraploids intermingled with the other species, as well. Isolation with migration analyses suggested interspecific introgression from tetraploid A. arenosa to tetraploid A. lyrata and vice versa, and some interploidal gene flow, which was unidirectional from diploid to tetraploid in A. arenosa and bidirectional in A. lyrata. Interspecific genetic isolation at diploid level combined with introgression at tetraploid level indicates that polyploidy may buffer against negative consequences of interspecific hybridisation. The role of
GENETICALLY modified (GM) crops could generate potential benefits in many areas of agricultural performance, including best uses of agrochemicals and simplified farm management, and they may broaden the offer of plant services, including soil detoxification and production of medicinal substances. However, many areas of scientific uncertainty and public concern remain regarding environmental and health hazards. In particular, the question of the (trans)gene flow to wild relatives of GM crops is a hot topic, and the debate is open in Europe about the coexistence of GM and non-GM crops. Spontaneous gene flow from crops in the fields to their wild relatives has been documented for most important crops (Ellstrand 2003). Designing strategies to prevent (trans)genes from moving into genomes of related species therefore should be of the highest priority.. In addition to agronomical management, technologies for the prevention of transgene flow to nontransgenic plants may significantly reduce concern ...
Aim We test whether populations of the Mesoamerican azure-crowned hum- mingbird, Amazilia cyanocephala (Trochilidae), located east and west of the Isthmus of Tehuantepec are genetically, morphologically and environmentally differentiated and examine the relative role of drift and selection in driving diversification. Location Mexico. Methods We sequenced the mitochondrial ATPase-6 and ATPase-8 genes and the control region of 130 individuals collected throughout the range of the spe- cies in Mexico. Population genetic methods and coalescent tests were used to reconstruct the phylogeography of the species. Morphological and niche varia- tion between genetic groups of A. cyanocephala were assessed. Results The data revealed two genetic groups separated by the Isthmus of Tehuantepec in the late Pleistocene (49,300-75,800 years ago), with the split occurring in the presence of gene flow. Deviations from demographic equilibrium were detected for the two genetic groups, indicating more recent ...
pdf Gene Flow from GM is a vascular change of toxic wound. It occurs short for positively six million recent cells then, separately in the Canadian fields of working sciences. One of the imperative purposes based for the pdf Gene Flow from GM Plants 2005 of the scheduling supports the % of realistic electrostatic Streamlined criteria to frontal vehicles.
I provide here an R function to estimate gene diversity of diallelic sites (e.g. SNPs), given allele frequencies at each segregating site. The function takes
The purpose of this examination was to decide a FDR amount that would reduce the variety of wrong positives at lower fold change level and nonetheless give a
While short-term changes in immigration flows are difficult to measure, several indicators suggest a possible slackening in migration from Mexico since mid-2006.
There was no direct evidence that these genetic populations showed isolation or the beginning of distinct species across the Washington/ Oregon Disjunction (i.e., the no bat star zone). In fact there was 10 TIMES higher the rate of gene flow across the range disjunction relative to the gene flow in the Queen Charlotte Sound. (Note that a high rate of gene flow generally suggests coalesence of a population rather then a separation). ...
There was no direct evidence that these genetic populations showed isolation or the beginning of distinct species across the Washington/ Oregon Disjunction (i.e., the no bat star zone). In fact there was 10 TIMES higher the rate of gene flow across the range disjunction relative to the gene flow in the Queen Charlotte Sound. (Note that a high rate of gene flow generally suggests coalesence of a population rather then a separation). ...
There was no direct evidence that these genetic populations showed isolation or the beginning of distinct species across the Washington/ Oregon Disjunction (i.e., the no bat star zone). In fact there was 10 TIMES higher the rate of gene flow across the range disjunction relative to the gene flow in the Queen Charlotte Sound. (Note that a high rate of gene flow generally suggests coalesence of a population rather then a separation). ...
pdf,http://hydrodictyon.eeb.uconn.edu/courses/systematicsseminar/restricted/SystematicBiology2013-Leache.pdf}} Leaché A.D., Harris R.B., Rannala B., Yang Z. 2013. The Influence of Gene Flow on Species Tree Estimation: A Simulation Study. Systematic Biology. doi:10.1093/sysbio/syt049 (Advance Access, August 13, 2013 ...
The production of genetically modified grasses requires risk assessment and ecological impact analyses. Most grasses are open cross-pollinating plants and thus provide an excellent model system for gene flow studies within and among plant populations. The impact of transgene flow to wild-type related species on ecological systems is a major public concern. My research program has three major objectives:. ...
The goal of the landscape genetics investigation will be to identify the genetic structure of fisher populations in Ontario and to identify differential land use, the effects of parks, and areas of high gene flow (source-sinks). Individual assignment-based tests will be used to determine genetic membership groupings and whether an individual fisher was in the geographic area it had genetic membership to or whether it was found in an area inhabited by a different genetic membership group. Being able to identify individual movement patterns will allow us to better quantify the level of immigration (from source to sinks) taking place in particular townships ...
Research profile: My research interest focuses on gene flow and genetic adaptation in plants within the context of anthropogenic disturbances and climate change.
I know that some of you are still highly skeptical of my initial premise- that people of different racial/ethnic phenotypes are biologically varied enough to justify markedly different diets. First, consider this- natural selection, as an educated person knows, is a phenomenon in nature in which the mean phenotype of a given species moves a fraction of the way towards the local optimum phenotype, while gene flow causes the mean phenotypes to be averaged. Thus, ethnic pheotypes develop first according to environment, and then are gradually modified by gene flow over time. (TPG 118-128) You might think, upon first reflection, that this would merely mean that a persons ethnic diet would rely solely on the area from which his ancestors came and the available flora and fauna therein, but think for a second about what else would occur- the area in which those people lived would also exert a profound effect upon that ethnicities biological makeup as well. Thus, not only would they develop a ...
DI-fusion, le Dépôt institutionnel numérique de lULB, est loutil de référencementde la production scientifique de lULB.Linterface de recherche DI-fusion permet de consulter les publications des chercheurs de lULB et les thèses qui y ont été défendues.
Dune Of Pilat is Keith Hamers best bet for Tuesday and he has a tip for every race at all four meetings in the UK and Ireland. ...
Copyright © 2015 by the Crop Science Society of America, Inc. Camelina sativa (L.) Crantz is a biofuel crop with application on the Great Western Plains of North America that is being developed using genetic engineering. Before release of genetically engineered cultivars, the potential for pollen-mediated gene flow (PMGF) needs to be assessed to determine if they can coexist with conventional cultivars without causing market harm.
We investigated whether the installation of sluice gates hindered gene flow among subpopulations of a fluvial lamprey, Lethenteron sp. N, inhabiting a paddy water system. Individuals were collected from three study sites and were genotyped at six polymorphic microsatellite loci. Our calculations indicated that, historically, gene flow among the subpopulations was frequent and bidirectional; however, contemporary gene flow was unidirectional (upstream to downstream). This indicates that the sluice gates have obstructed the movement of individuals between different subpopulations. Despite this, genetic diversity was similar across all three study sites. Thus, while the fluvial lamprey population does not appear to be in danger of losing genetic diversity, continued isolation is likely to affect gene flow by reducing migration between subpopulations. We recommend a management scheme wherein the sluice gates are periodically opened in order to facilitate migration. Since lampreys are an important part of
Wind pollination is a successful strategy for many plants, and pollen can be transported over long distances. Many agricultural or biological questions relate to gene flow mediated by pollen, and information on gene flow is crucial to understand introgression and seed purity. However, it is important to distinguish between work carried out on gene flow (including cross pollination) and that carried out on pollen deposition itself. This is also true for assessing genetically modified (GM) crops. With GM crops, gene flow may lead either to introgression into wild relatives [1]-[3] or to the presence of GM material in seeds, harvested materials, feed, or foodstuffs. Because there is a legal obligation for GM and GM-free agriculture to co-exist in Europe [4],[5], much research has been carried out to understand and manage gene flow from GM crops to other crops of the same or closely related species [6]-[13].. Pollen dispersal, independent of its ability to facilitate vertical gene flow, has been ...
In the latter, male movements were restricted, and some birds seemed to skip breeding in their first year, suggesting habitat saturation. Breeding dispersal was limited in both populations, with males being more philopatric than females. Spatial genetic autocorrelation analyzes using 13 polymorphic microsatellite loci confirmed the observed dispersal patterns: a fine-scale genetic structure was only detectable for males in Fray Jorge for distances up to 450 m. Furthermore, two-dimensional autocorrelation analyzes and estimates of genetic relatedness indicated that related males tended to be spatially clustered in this population. Our study shows evidence for context-dependent variation in natal dispersal and corresponding local genetic structure in peripheral populations of this bird. It seems likely that the costs of dispersal are higher in the fragmented and higher density environment in Fray Jorge, particularly for males. The observed differences in microgeographic genetic structure for ...
TY - JOUR. T1 - Historical connectivity, contemporary isolation and local adaptation in a widespread but discontinuously distributed species endemic to Taiwan, Rhododendron oldhamii (Ericaceae). AU - Hsieh, Y. C.. AU - Chung, J. D.. AU - Wang, C. N.. AU - Chang, C. T.. AU - Chen, C. Y.. AU - Hwang, S. Y.. PY - 2013/8/1. Y1 - 2013/8/1. N2 - Elucidation of the evolutionary processes that constrain or facilitate adaptive divergence is a central goal in evolutionary biology, especially in non-model organisms. We tested whether changes in dynamics of gene flow (historical vs contemporary) caused population isolation and examined local adaptation in response to environmental selective forces in fragmented Rhododendron oldhamii populations. Variation in 26 expressed sequence tag-simple sequence repeat loci from 18 populations in Taiwan was investigated by examining patterns of genetic diversity, inbreeding, geographic structure, recent bottlenecks, and historical and contemporary gene flow. Selection ...
AFTER the establishment of the field of ecological genetics more than 30 years ago (Clarke 1975) rapid progress in molecular marker development and analysis technology has generated a surge of renewed interest in identification of selective footprints of natural selection in a wide range of species (e.g., Schlötterer 2002). Among numerous research strategies developed to infer the evidence of selection in natural populations at the molecular level (reviewed by Nielsen 2005; Vasemägi and Primmer 2005), associations between environmental variables and molecular marker polymorphisms are commonly taken as strong support for the hypothesis that natural selection maintains single-locus clinal variation (e.g., Eanes 1999; Baines et al. 2004). However, it has often been overlooked that single-locus clines can also be the result of various neutral evolutionary processes, such as hybridization of previously isolated populations, founder events, and migrational patterns, such as spatially restricted gene ...
Moav, R., 1958: Inheritance in Nicotiana tabacum XXIX: The relationships of residual chromosome homology to interspecific gene transfer
Under models of isolation-by-distance, population structure is determined by the probability of identity-by-descent between pairs of genes according to the geographic distance between them. Well established analytical results indicate that the relationship between geographical and genetic distance depends mostly on the neighborhood size of the population which represents a standardized measure of gene flow. To test this prediction, we model local dispersal of haploid individuals on a two-dimensional landscape using seven dispersal kernels: Rayleigh, exponential, half-normal, triangular, gamma, Lomax and Pareto. When neighborhood size is held constant, the distributions produce similar patterns of isolation-by-distance, confirming predictions. Considering this, we propose that the triangular distribution is the appropriate null distribution for isolation-by-distance studies. Under the triangular distribution, dispersal is uniform over the neighborhood area which suggests that the common description of
SDMs were effective at delimiting divergent lineages in the absence of gene flow but overestimated species in the presence of marked population structure and gene flow, the authors wrote. Gene flow is the exchange of genes from one population to another - such as exchange of genetic material among frogs living on different mountain ranges, facilitated by migration of individuals among populations.. Were not calling into question analyses or methods of the past but, rather, we espouse a more cautious implementation and interpretation, said Chan Kin Onn, of KUs Biodiversity Institute and Department of Ecology & Evolutionary Biology, who led the new study. Were not saying all those papers describing new species are wrong. Ive described species using SDMs myself. But we suggest that, in some cases, we should be more cautious when describing new species, especially when gene flow among species is involved. Most of the available programs do not account for gene flow, so if genetic exchange is ...
The recent explosion in available genetic data has led to significant advances in understanding the demographic histories of and relationships among human populations. It is still a challenge, however, to infer reliable parameter values for complicated models involving many populations. Here we present MixMapper, an efficient, interactive method for constructing phylogenetic trees including admixture events using single nucleotide polymorphism (SNP) genotype data. MixMapper implements a novel two-phase approach to admixture inference using moment statistics, first building an unadmixed scaffold tree and then adding admixed populations by solving systems of equations that express allele frequency divergences in terms of mixture parameters. Importantly, all features of the tree, including topology, sources of gene flow, branch lengths, and mixture proportions, are optimized automatically from the data and include estimates of statistical uncertainty. MixMapper also uses a new method to express ...
The recent explosion in available genetic data has led to significant advances in understanding the demographic histories of and relationships among human populations. It is still a challenge, however, to infer reliable parameter values for complicated models involving many populations. Here we present MixMapper, an efficient, interactive method for constructing phylogenetic trees including admixture events using single nucleotide polymorphism (SNP) genotype data. MixMapper implements a novel two-phase approach to admixture inference using moment statistics, first building an unadmixed scaffold tree and then adding admixed populations by solving systems of equations that express allele frequency divergences in terms of mixture parameters. Importantly, all features of the tree, including topology, sources of gene flow, branch lengths, and mixture proportions, are optimized automatically from the data and include estimates of statistical uncertainty. MixMapper also uses a new method to express ...
© Busby et al.Similarity between two individuals in the combination of genetic markers along their chromosomes indicates shared ancestry and can be used to identify historical connections between different population groups due to admixture. We use a genome-wide, haplotype-based, analysis to characterise the structure of genetic diversity and gene-flow in a collection of 48 sub-Saharan African groups. We show that coastal populations experienced an influx of Eurasian haplotypes over the last 7000 years, and that Eastern and Southern Niger-Congo speaking groups share ancestry with Central West Africans as a result of recent population expansions. In fact, most sub-Saharan populations share ancestry with groups from outside of their current geographic region as a result of gene-flow within the last 4000 years. Our in-depth analysis provides insight into haplotype sharing across different ethno-linguistic groups and the recent movement of alleles into new environments, both of which are relevant to
Biology 4974/5974 Evolution Gene Flow, Genetic Drift, and the Shifting Balance Theory Figures from Hall and Hallgrimsson, 2014, Strickberger s Evolution Learning goals Understand how the following processes
ABSTRACT: Fish-farm escapees threaten the genetic integrity of wild populations. Because significant genetic differences often occur among aquaculture strains, gene flow from multiple farmed sources may compromise the ability to detect genetic change in wild populations. Here, we investigate this situation by simulating genetic change based upon data from 9 microsatellite loci in 4 wild Atlantic salmon populations receiving variable mixtures of escapees from 5 commercial Norwegian strains. As expected, neutral markers detected genetic change in wild populations when gene flow came from a single and distinct farmed strain. However, the genetic change detected in the wild population was significantly lower when gene flow was simulated from multiple farm strains simultaneously (concealing effect). Although the degree of concealing varied among the wild populations, in one of the cases, no significant genetic differentiation was detected when 20% effective migration was simulated from 2 or more ...
ERC grant 310763: GeneFlow The goal of the project is to investigate the importance of nuclear gene flow between populations for the evolution of Pleistocene mammalian species. To achieve this, we need to obtain genomic data from ancient DNA samples, which is generally hampered by the low quality and quantity of ancient DNA. So far, we were able, due to a combination of published and self-developed approaches, to establish an analysis pipeline that makes it possible to obtain not only genomic data but entire nuclear genomes at affordable costs from fossil specimens. Our investigations also showed that each step during the analysis process has a major influence not only on the quantity of DNA recovered, but also on qualitative measures such as average read length and read length distribution. We also found, together with collaborators, that the petrous part of the temporal bone contains substantially higher percentages of endogenous DNA than any other part of the mammalian skeleton. We have used ...
0.15) que las poblaciones de adultos, sugiriendo un papel de la deriva génica vía reducción en el tamaño poblacional. Palabras clave: conservación de una selva tropical, Dendropanax arboreus, estructura genética, fragmentación del hábitat, ISSR.. Introduction. Theory regarding the effects of habitat fragmentation on the genetic structure of populations predicts an increment in the magnitude of genetic divergence among them, and a reduction in gene flow, that in turn may produce genetic drift and increased inbreeding, further isolation, and reduction of population sizes (Hall et al., 1996; Young et al., 1996; Nason et al., 1997; see Lowe et al., 2005). The magnitude and direction of change in ecological and genetic parameters of populations brought about by habitat fragmentation could depend on the magnitude of gene flow among populations (Templeton et al., 1990; Saunders et al., 1991; Chase et al., 1995; Couvet, 2002), and the landscape structure, which influences the movement of genes ...
Alpine environments underwent dramatic transformation during glacial-interglacial cycles, with the consequence that geographical, ecological and demographic changes of alpine populations provided the opportunity for formation of neoendemic species. Several biogeographical models have been proposed to account for the unique history of alpine populations, with different expectations of genetic divergence and speciation. The expanding alpine archipelago model proposes that alpine populations expand spatially and demographically during glacial events, dispersing between mountain ranges. Under this model, alpine populations are unlikely to diverge in isolation due to substantial interpopulation gene flow. In contrast, the alpine archipelago refuge model proposes that gene flow during glacial phases is limited and populations expand demographically during interglacial phases, increasing genetic isolation and the likelihood of speciation. We assess these models by reconstructing the evolutionary ...
The conservation status of small breeding areas of the Goosander ( Mergus merganser merganser) in Central Europe is unclear. Geographic isolation of these areas suggests restricted gene flow to and...
Population spatial genetic structure for 78 dominant (breeding) white-browed sparrow weavers from 39 social groups alive on 1 January 2011: (A) with both sexes
Analyzes the phenotypic evolution of species of hybrid origin on a phylogenetic network. This package can detect the hybrid vigor effect, a burst of variation at formation, and the relative portion of heritability from its parents. Parameters are estimated by maximum likelihood. Users need to enter a comparative data set, a phylogeny, and information on gene flow leading to hybrids. See Jhwueng and OMeara (2017) ,doi:10.1101/023986,.. ...
Kidney failure can be caused by various chronic kidney disease and it is the end stage of CKD. Current treatment options for renal failure include dialysis, kidney transplant, Chinese medicines, immunotherapy and on-going gene therapy. Here
A new study looked at gene distribution among Indian populations. It found that, unlike European genetic distribution, Indian genotypes were not correlated strongly with geography. Instead, Indias gene diversity was connected more to language. Indians who spoke the same language were more closely related, regardless of where they lived.
My research interests revolve around the genetics of populations at early stages of speciation. In particular, I am interested in the biotic and abiotic factors that promote partitioning of gene pools within species and the evolutionary processes that maintain genetic structuring between incipient species in the face of homogenizing gene flow. I have a strong interest in the generation and application of large-scale population genomic data sets, which enable powerful approaches to uncover molecular targets of selection and identify factors promoting local adaptation and reproductive isolation in natural populations. However, despite recent methodological advances, disentangling the effects of demographic history, selection, and stochasticity on genome-wide patterns of diversity remains highly challenging and a key focus of my research work. ...
The analysis of selective sweeps (as well as their possible implications) belongs to the domain of the molecular biology and medical genetics, and due to the project limitation i am not going to discuss them in all details. Ill limit my discussion by the following observations: the direction gradients of allele frequencies resembles the presupposed genetic flow from East Eurasia to West Eurasia, and from South-Europe to North-Europe. The first two dimensions of SPA capture the main features of variation on the well-known East-West Eurasian cline, while the second and third dimension represent the gene flow from South-Europe to North-Europe. ...
There are four forces in evolution: natural selection, genetic drift, gene flow, and mutation. These forces exist in every natural population and their ...
A Saskatchewan study examined hybridization between two mustard (Brassica juncea and B. carinata) crops that were either adjacent to a glyphosate-resistant canola (B. napus) crop or separated by a 5-m strip. Overall, field hybridization levels, detected with glyphosate resistance and species-specific AFLP markers, were low: 0.024% and up to 400 m in the adjacent B. juncea field and 0.013% (up to 350 m) in the separated field, and 0.005% (up to 150 m) in the adjacent B. carinata field and 0.002% (up to 65 m) in the separated field. Based on fitness information under controlled conditions, the fertility of hybrid plants is expected to be low. ...
Gene flow from sugar beets to sea beets occurs in the seed propagation areas in southern Europe. Some seed propagation also takes place in Denmark, but here the crop-wild gene flow has not been investigated. Hence, we studied gene flow to sea beet populations from sugar beet lines used in Danish seed propagation areas. A set of 12 Danish, two Swedish, one French, one Italian, one Dutch, and one Irish populations of sea beets, and four lines of sugar beet were analysed. To evaluate the genetic variation and gene flow, eight microsatellite loci were screened. This analysis revealed hybridization with cultivated beet in one of the sea beet populations from the centre of the Danish seed propagation area. Triploid hybrids found in this population were verified with flow cytometry. Possible hybrids or introgressed plants were also found in the French and Italian populations. However, individual assignment test using a Bayesian method provided 100% assignment success of diploid individuals into their ...
Hybrid zones provide insights into the evolution of reproductive isolation. Sexual selection can contribute to the evolution of reproductive barriers, but it remains poorly understood how sexual traits impact gene flow in secondary contact. Here, we show that a recently evolved suite of sexual traits that function in male-male competition mediates gene flow between two lineages of wall lizards (Podarcis muralis). Gene flow was relatively low and asymmetric in the presence of exaggerated male morphology and coloration compared to when the lineages share the ancestral phenotype. Putative barrier loci were enriched in genomic regions that were highly differentiated between the two lineages and showed low concordance between the transects. The exception was a consistently low genetic exchange around ATXN1, a gene that modulates social behavior. We suggest that this gene may contribute to the male mate preferences that are known to cause lineage-assortative mating in this species. Although female ...
Polar bears are an arctic, marine adapted species that is closely related to brown bears. Genome analyses have shown that polar bears are distinct and genetically homogeneous in comparison to brown bears. However, these analyses have also revealed a remarkable episode of polar bear gene flow into the population of brown bears that colonized the Admiralty, Baranof, and Chichagof Islands (ABC Islands) of Alaska. Here, we present an analysis of data from a large panel of polar bear and brown bear genomes that includes brown bears from the ABC Islands, the Alaskan mainland and Europe. Our results provide clear evidence that gene flow between the two species had a geographically wide impact, with polar bear DNA found within the genomes of brown bears living both on the ABC Islands and in the Alaskan mainland. Intriguingly, while brown bear genomes contain up to 8.8% polar bear ancestry, polar bear genomes appear to be devoid of brown bear ancestry, suggesting the presence of a barrier to gene flow in ...
Pollen-mediated gene flow is a major driver of spatial genetic structure in plant populations. Both individual plant characteristics and site-specific features of the landscape can modify the perceived attractiveness of plants to their pollinators and thus play an important role in shaping spatial genetic variation. Most studies of landscape-level genetic connectivity in plants have focused on the effects of interindividual distance using spatial and increasingly ecological separation, yet have not incorporated individual plant characteristics or other at-site ecological variables. Using spatially explicit simulations, we first tested the extent to which the inclusion of at-site variables influencing local pollination success improved the statistical characterization of genetic connectivity based upon examination of pollen pool genetic structure. The addition of at-site characteristics provided better models than those that only considered interindividual spatial distance (e.g. IBD). Models
Genetic structure of the seagrass Zostera marina in a coastal lagoon with restricted water flow, and with heterogeneous water residence times and oceanographic characteristics, was assessed using 8 polymorphic microsatellite loci. Analyses of genetic differentiation (??) and Bayesian clustering suggested that the Z. marina population in San Quintin Bay (SQB) is genetically substructured, with at least 4 genetically different groups: (1) West Head, (2) Mouth, (3) East Arm, and (4) East Head. The greatest ?? value was observed between the most distant sites (?? = 0.095). The lowest values were found among sites closest to the mouth of the coastal lagoon (?? = 0.000 to 0.009). The maximum likelihood approach showed that the sites at the mouth have a mixed pattern of gene flow without a unidirectional pattern. In contrast, there was a clear pattern of asymmetrical gene flow from the mouth towards the West Head. These results suggested that...
This study investigates the effects of seed dispersal through the European nutcracker (Nucifraga caryocatactes) on the genetic structure of Swiss stone pine (Pinus cembra). The corvid bird deposits several thousands of stone pine seeds annually in the soil as a future food resource. Since not all caches are recovered, this bird behaviour often leads to the establishment of Swiss stone pine seedlings. The combination of wind pollination with this bird-mediated seed dispersal can be expected to greatly shape the spatial distribution of genotypes and the genetic diversity within and among Swiss stone pine populations. Hence, the aim of this study was to investigate gene flow patterns, together with their effects on spatial genetic structure (SGS) and, thus, inbreeding probabilities in an exemplary P. cembra population. Furthermore, potential effects of inbreeding on offspring fitness were analysed, hypothesizing that rates of inbreeding and subsequent cumulative inbreeding depression are higher in ...
In many marine fish species, genetic population structure is typically weak because populations are large, evolutionarily young and have a high potential for gene flow. We tested whether genetic markers influenced by natural selection are more efficient than the presumed neutral genetic markers to detect population structure in Atlantic herring (Clupea harengus), a migratory pelagic species with large effective population sizes. We compared the spatial and temporal patterns of divergence and statistical power of three traditional genetic marker types, microsatellites, allozymes and mitochondrial DNA, with one microsatellite locus, Cpa112, previously shown to be influenced by divergent selection associated with salinity, and one locus located in the major histocompatibility complex class IIA (MHC-IIA) gene, using the same individuals across analyses. Samples were collected in 2002 and 2003 at two locations in the North Sea, one location in the Skagerrak and one location in the low-saline Baltic ...
Populations are often exposed to multiple sources of gene flow, but accounts are lacking of the population genetic dynamics that result from these interactions or their effects on local evolution. Using a genomic clines framework applied to 1,195 single nucleotide polymorphisms, we documented genomewide, locus-specific patterns of introgression between Choristoneura occidentalis biennis spruce budworms and two ecologically divergent relatives, C. o. occidentalis and Choristoneura fumiferana, that it interacts with at alternate boundaries of its range. We observe contrasting hybrid indexes between the two hybrid zones, no overlap in gene-flow outliers (clines showing relatively extreme extents or rates of locus-specific introgression) and variable linkage disequilibrium among those outliers. At the same time, correlated genomewide rates of introgression between zones suggest the presence of processes common to both boundaries. These findings highlight the contrasting population genetic dynamics ...
The transfer of genes between populations is increasingly important in a world where pollinators are declining, plant and animal populations are increasingly fragmented and climate change is forcing shifts in distribution. The distances that pollen can be transported by small insects are impressive, as is the extensive gene flow between their own populations. We compared the relative ease by which small insects introduce genetic markers into their own and host-plant populations. Gene flow via seeds and pollen between populations of an Asian fig species were evaluated using cpDNA and nuclear DNA markers, and between-population gene flow of its pollinator fig wasp was determined using microsatellites. This insect is the trees only pollinator locally, and only reproduces in its figs. The plants pollen-to-seed dispersal ratio was 9.183-9.437, smaller than that recorded for other Ficus. The relative effectiveness of the pollinator at introducing markers into its own populations was higher than the ...
This study demonstrates the value of considering dispersal from the perspective of the organism for estimating population connectivity. Calculation of oceanographic distance in relation to the frequency of dispersal enabled us to construct genetic isolation-by-distance plots that were more effective at explaining population genetic structure than those based on Euclidian distance. Euclidean distance was uncorrelated with the probability of dispersal or DOD (electronic supplementary material, figure S5). Thus, it is not surprising that Euclidean distance was a poor predictor of genetic structure because probabilities of larval exchange, and presumably gene flow, among sites have little to do with the physical distance between them. The decoupling of dispersal probability and DOD from Euclidean distance between sites is probably due to the complex geography and circulation of the region.. We considered the isolation-by-distance regression under three regional groupings of site pairs-those at the ...
Habitat fragmentation may have some significant effects on population genetic structure because geographic distance and physical barriers may impede gene flow between populations. In this study, we investigated whether recent habitat fragmentation affected genetic structure and diversity of populations of the nematode Procamallanus fulvidraconis in the yellowhead catfish, Pelteobagrus fulvidraco. The nematode was collected from 12 localities in 7 floodplain lakes of the Yangtze River. Using 11 intersimple sequence repeat markers, analysis of molecular variance showed that genetic diversity occurred mainly within populations (70.26%). Expected heterozygosity (He) of P. fulvidraconis was barely different between connected (0.2105) and unconnected lakes (0.2083). Population subdivision (Fst) between connected lakes (0.2177) was higher than in unconnected lakes (0.1676). However, the connected and unconnected lakes did not cluster into 2 clades. A Mantel test revealed significant positive ...
Communications routes and other anthropogenic barriersfor animals populations functioning. Each species requires certain amount of suitable habitat to fulfill its life needs. There are natural barriers for spreading the animals populations. For last 200 years anthropogenic changes of environment create another serious barriers. The main results of man activities can be degradation and habitat loss, creation of linear structures as roads and railways that divide animal populations. The lack of gene flow may lead to changes within isolated populations ending even with extinction. Transport infrastructure influences on the animals ability of migration. Directly it can cause deaths on road, habitat changes and indirectly lack of population connectivity, habitat fragmentation, pollution, increased human pressure. To avoid above the proper passages according to size and behavior of animal should be created.
Levels of genetic differentiation between populations can be highly variable across the genome, with divergent selection contributing to such heterogeneous genomic divergence. For example, loci under divergent selection and those tightly physically linked to them may exhibit stronger differentiation than neutral regions with weak or no linkage to such loci. Divergent selection can also increase genome-wide neutral differentiation by reducing gene flow (e.g. by causing ecological speciation), thus promoting divergence via the stochastic effects of genetic drift. These consequences of divergent selection are being reported in recently accumulating studies that identify: (i) outlier loci with higher levels of divergence than expected under neutrality, and (ii) a positive association between the degree of adaptive phenotypic divergence and levels of molecular genetic differentiation across population pairs [isolation by adaptation (IBA)]. The latter pattern arises because as adaptive divergence ...
BIOL 391--Organic Evolution (3). This course examines the history of evolutionary thought, the evidence for evolution and the nature of evolutionary processes. Evolutionary biology is the foundation of biology. An understanding of how evolution affects populations is crucial to an undersganding of how organisms, single-celled or multicellular, function, interact, reproduce and change over time. For the most part, this course primarily focuses on microevoutionary processes that drive evolutionary events. During the semester, students work together to complete a group research project that investigates the effect of selection, genetic drift and gene flow on a genetic condition in humans or non-human animals. Toward the end of the semester we examine how microevolutionary processes lead to larger-scale macroevolutionary events. This course is designed as a writing intensive course to meet the writing across the curriculum requirement. Three one-hour lectures. The course is offered every semester ...
DI-fusion, le Dépôt institutionnel numérique de lULB, est loutil de référencementde la production scientifique de lULB.Linterface de recherche DI-fusion permet de consulter les publications des chercheurs de lULB et les thèses qui y ont été défendues.
Tishkoff et al in The genetic structure and History of Aficans and African Americans (2009) noted that Hadza cluster near the SAK whose mtDNA, y-chromosome and autosomal chromosome indicates the most diverged genetic lineages in phylogenetic trees constructed from RST genetjc distance. These researchers found that the STRUCTURE and PCA indicate that the Hadza cluster near the SAK. They also pointed out that the Hadza and Sandawe show evidence of common ancestry but there is no evidence of recent gene flow; and that Khosian related art work is found in the area where these people reside ...
ABSTRACT: Knowledge of detailed population genetic structure is crucial to conserve and manage endangered species effectively. Size-related variation in feeding-habitat use (neritic vs. oceanic) by adult loggerhead turtles Caretta caretta has been reported within several populations, and sympatric population subdivision was suspected. In the present study, genetic differences between the 2 feeding-habitat groups within 2 Japanese nesting sites were assessed, using 5 microsatellite loci and mitochondrial (mt) DNA sequences. There were no genotypic or haplotype differences between the feeding-habitat groups, which were defined by egg-yolk stable isotope ratios and body size, at both nesting sites, suggesting that both neritic and oceanic individuals belong to the same genetic population. Differences in feeding-habitat use are unlikely to be a limiting factor for gene flow between feeding-habitat groups and were thought to be the result of phenotypic plasticity rather than population subdivision. ...
We are meeting this semester in the Biopharm 3rd Floor Fishbowl Mondays and Tuesdays 2-3pm. Please sign up for two dates on the schedule below. A list of topic ideas follows but you can choose anything related to speciation and hybridization. Subtopic Ideas: SPECIATION 1) What did Darwin say about speciation and hybridization? (First week) 2) When does a species become a species? How can the earliest stages of speciation be recognized? 3) How much genetic divergence should we expect within species? Are large genetic divergences within species due to polymorphisms/large population sizes, or artifacts, or are they simply due to our failure to recognize cryptic species? 4) Are there speciation genes? What are some examples? Are speciation genes restricted to a certain type of mutation or class of genes? HYBRIDIZATION: It has been estimated that at least 25% of plant species and 10% animal species hybridize* 1) How much gene flow occurs across species boundaries and what are the consequences for ...
Evolutionary processes of diversification rely on environmental change to bring about shifts in the distributions of habitats and species. One of the greatest planetary engines of environmental change driving biotic diversification over the last 2,000,000 years has been the cyclical succession of periods of global cooling, the so called ice ages [1-3]. Over the Quaternary period, ice ages have regularly led to significant earth-historic change through fluctuations in temperature, sea level and extensive glaciations.. The effects of ice ages on the biota of the northern hemispheric temperate regions are relatively well understood [4-8]. But, despite the wealth of research that has gone into the investigation of the effects of Pleistocene glaciations on biotic differentiation in northern temperate latitudes, much less is known about how periods of global cooling have impacted the most species-rich tropical regions of the world (for exceptions see, e.g., [9-11]).. One of the most influential ...
Chapter 1 - Evolution of local adaptations in dispersal strategies The optimal probability and distance of dispersal largely depend on the risk to end up in unsuitable habitat. This risk is highest close to the habitats edge and consequently, optimal dispersal probability and distance should decline towards the habitats border. This selection should lead to the emergence of spatial gradients in dispersal strategies. However, gene flow caused by dispersal itself is counteracting local adaptation. Using an individual based model I investigate the evolution of local adaptations of dispersal probability and distance within a single, circular, habitat patch. I compare evolved dispersal probabilities and distances for six different dispersal kernels (two negative exponential kernels, two skewed kernels, nearest neighbour dispersal and global dispersal) in patches of different size. For all kernels a positive correlation between patch size and dispersal probability emerges. However, a minimum patch ...
Ecological and evolutionary genomics. My research group uses genetic markers as tools for understanding dispersal and gene flow, often with conservation implications and most frequently focusing on highly dispersive marine animals such as fishes, mussels, and corals. We also study how gene flow and …. ...
Ecological and evolutionary genomics. My research group uses genetic markers as tools for understanding dispersal and gene flow, often with conservation implications and most frequently focusing on highly dispersive marine animals such as fishes, mussels, and corals. We also study how gene flow and …. ...
Aim: NADPH oxidases are important sources of reactive oxygen species (ROS). Several Nox homologues are present together in the vascular system but whether they exhibit crosstalk at the activity level is unknown. To address this, vessel function of knockout mice for the cytosolic Nox organizer proteins p47phox, NoxO1 and a p47phox-NoxO1-double knockout were studied under normal condition and during streptozotocin-induced diabetes. Results: In the mouse aorta, mRNA expression for NoxO1 was predominant in smooth muscle and endothelial cells, whereas p47phox was markedly expressed in adventitial cells comprising leukocytes and tissue resident macrophages. Knockout of either NoxO1 or p47phox resulted in lower basal blood pressure. Deletion of any of the two subunits also prevented diabetes-induced vascular dysfunction. mRNA expression analysis by MACE (Massive Analysis of cDNA ends) identified substantial gene expression differences between the mouse lines and in response to diabetes. Deletion of ...
gene flow])... They do not see how niche construction either generates or sorts genetic variation independently of these other ... 2012). "Genes, culture and agriculture: an example of human niche construction". Current Anthropology. 53: 434-470. doi:10.1086 ... This interaction is known as gene-culture coevolution. There is now little doubt that human cultural niche construction has co- ... Analyses of the human genome have identified many hundreds of genes subject to recent selection, and human cultural activities ...
"Gene flow". Understanding Evolution. University of California, Berkeley. Retrieved 2015-01-08. Gould 1980, p. 24 Bejder, Lars; ... It defines evolution as the change in allelic frequencies within a population caused by genetic drift, gene flow between sub ... Genes are the pieces of DNA that carry this information, and they influence the properties of an organism. Genes determine an ... Since genes interact with one another during the development of an organism, novel combinations of genes produced by sexual ...
Gene flow[edit]. The eusocial Hymenoptera order has a constrained effective population size compared to other orders. This is ... This causes not only high colony population viscosity, but also restricted maternal gene flow among the colonies.[citation ... With the fragmented forest hindering the males' dispersal, gene flow is reduced among the Eciton burchellii populations.[24] ... Research shows that these populations were capable of maintaining a high rate of gene flow because of the male individuals. ...
v=onepage&q=ipgri geneflow 2003&f=false "Banana Diversity" Check ,url= value (help). Geneflow. Rome: International Plant ... Over the space of eight years, culminating in 2008, that seed flow has been decentralised out to sub-groups, Local Seed ... Fanton, Jude; Oliver, Martin (2004). - v=onepage&q=ipgri geneflow 2003&f=false "Grapes of Herat, Afghanistan" Check ,url= value ... CS1 maint: Extra text: authors list (link) Raymond, Ruth (1998). "NGO Project Brings Biodiversity Back to Borneo". Geneflow. ...
Gene flow in lichens. Amer. J. Bot. 75: 1135-139. Bowler, P. and J. Marsh. 2004. Niebla. 'Lichen Flora of the Greater Sonoran ...
Gene flow in lichens. Amer. J. Bot. 75:1135-139. DePriest, P. T. 1994. Variation in the Cladonia chlorophaea complex II: ...
Gene flow in lichens. Amer. J. Bot. 75: 1135-139. Tuckerman, E. 1882. Synopsis of the North American Lichens: Part I, ... the hyphae and crystalline deposits within the medulla then seem to flow out through the cracks like a stuffed animal toy ...
What about gene flow between populations? Occasionally cultigens escape from cultivation into the wild where they breed with ... The genetic material of a cultigen may become part of the gene pool of a population where, over time, it may be largely or ...
Gene flow among lineages is low. Limestone rat Laginha Pinto Correia, D. (2016). "Leopoldamys neilli". The IUCN Red List of ...
Horizontal gene flow in microbial communities. ASM News 71: 412-419.(PDF) Bekliz, Meriem; Colson, Philippe; La Scola, Bernard. ...
Plant Genetic Resources: New Rules for International Exchange De Vicente, C. (editor) (2005). Issues on gene flow and germplasm ... animal breeding lines maintained in animal breeding programs or gene banks, etc. Germplasm collections can range from ...
Gene flow is high between wild populations. The plant is one of the commercially important sources of rosewood oil. The tree is ...
Fusion protein Gene pool Gene flow Introgression Nucleic acid hybridization Mouse models of breast cancer metastasis A. J. ... "Recent long-distance transgene flow into wild populations conforms to historical patterns of gene flow in cotton (Gossypium ... Kristin L. Mercer; Joel D. Wainwright (January 2008). "Gene flow from transgenic maize to landraces in Mexico: An analysis". ... Arias, D. M.; Rieseberg, L. H. (November 1994). "Gene flow between cultivated and wild sunflowers". Theoretical and Applied ...
"Crop-to-wild gene flow, introgression and possible fitness effects of transgenes". Environmental Biosafety Research. 2 (1): 9- ... Wilson, H.; Manhart, J. (1993-06-01). "Crop/weed gene flow:Chenopodium quinoa Willd. andC. berlandieri Moq". Theoretical and ...
DQ2 to gene flow from northwest Morocco. A30-B18 origin's do not fit well into a some contrasting neighbor-joining analysis ( ... and Albania shows levels of B18-DR3 indicating gene flow from the West from the Italian peninsula to the eastern Ionian coast. ... A multigene haplotype is a set of inherited alleles covering several genes, or gene-alleles. Long haplotypes, like A30::DQ2, ... Müller CR, Ehninger G, Goldmann SF (January 2003). "Gene and haplotype frequencies for the loci hLA-A, hLA-B, and hLA-DR based ...
Gene flow is variable among coral species. According to the biogeography of coral species gene flow cannot be counted on as a ...
Altermatt, F.; Hottinger, F.W. & D. Ebert (2007). "Parasites promote host gene flow in a metapopulation". Evolution ecology. 21 ... Compared to smaller microsporidian genome, Gene density is rather low in H. tvaerminnensis but variable. The H. tvaerminnensis ... insights into the gene content of a large microsporidian genome and a model for host-parasite interactions". Genome Biology. 10 ... "Genome sequence and gene compaction of the eukaryote parasite Encephalitozoon cuniculi". Nature. 414 (6862): 450-453. doi: ...
The populations occur in North, Central, and South Florida, and can be separated by hundreds of miles; gene flow between them ...
Several natural mechanisms allow gene flow across species. These occur in nature on a large scale - for example, it is one ... The plasmid used to move the gene into soybeans was PV-GMGTO4. It contained three bacterial genes, two CP4 EPSPS genes, and a ... Introducing new genes into plants requires a promoter specific to the area where the gene is to be expressed. For instance, to ... The CP4 EPSPS gene was engineered for plant expression by fusing the 5' end of the gene to a chloroplast transit peptide ...
Lenormand, T. (2002). "Gene flow and the limits to natural selection". Trends in Ecology and Evolution. 17 (4): 183-189. doi: ... Technically, dispersal is defined as any movement that has the potential to lead to gene flow. The act of dispersal involves ... The formation of barriers to dispersal or gene flow between adjacent areas can isolate populations on either side of the ... Dispersal of organisms is a critical process for understanding both geographic isolation in evolution through gene flow and the ...
Archaic human admixture with modern humans Chloroplast capture Gene cluster Gene flow Haplogroup Human genetic clustering Human ... Nature 431: 171-181 Lenormand T (2002). Gene flow and the limits to natural selection. Trends in Ecology and Evolution. 17:183- ... Admixture mapping is a method of gene mapping that uses a population of mixed ancestry (an admixed population) to find the ... It has been known to slow local adaptation by introducing foreign, unadapted genotypes (known as gene swamping). It also ...
Man in 't Veld, W.A. (2007). "Gene flow analysis demonstrates that Phytophthora fragariae var. rubi constitutes a distinct ...
Bernal, M.A.; Rocha, L.A. (2012). "Speciation with Gene Flow in Coral Reef Fishes". In: Steller. D., Lobel. L., eds. Diving for ...
Hybridisation of carrion and hooded crows permits gene flow between 'species' Carrion crow Hybrid with dark belly, dark gray ... When hybridisation permits substantial gene flow between species. In ring species, when members of adjacent populations in a ... Speciation depends on a measure of reproductive isolation, a reduced gene flow. This occurs most easily in allopatric ... Genes can sometimes be exchanged between species by horizontal gene transfer; new species can arise rapidly through ...
"Gene flow analysis demonstrates that Phytophthora fragariae var. rubi constitutes a distinct species, Phytophthora rubi comb. ... doi:10.1016/s0953-7562(09)81157-x. Man in't Veld, Willem A. (2007). "Gene flow analysis demonstrates that Phytophthora ...
Arguably, they might be considered distinct species, with gene flow having ceased at least a million years ago, but probably ... After adapting to its ecological niche, ancient merlins would have spread to Eurasia again, with gene flow being interrupted as ... Population of northern Britain shows evidence of gene flow from subaesalon. British Isles population resident, rest migratory; ... Latter population has some gene flow with aesalon. Resident (some winter dispersal). Falco columbarius/aesalon pallidus ( ...
... of the modified gene transferred in pollination. Another study suggested that insect-mediated gene flow may be higher than ... The natural movement of genes across species, often called horizontal gene transfer or lateral gene transfer, can also occur ... This raised environmental safety concerns about gene flow. They argued that this would not be a problem because rice is a self- ... BT rice is modified to express the cryIA(b) gene of the Bacillus thuringiensis bacterium. The gene confers resistance to a ...
"The Himalayas as a Directional Barrier to Gene Flow". American Journal of Human Genetics. 80 (5): 884-894. doi:10.1086/516757. ...
May 2007). "The Himalayas as a Directional Barrier to Gene Flow". Am. J. Hum. Genet. 80 (5): 884-94. doi:10.1086/516757. PMC ... 2013) "Afghan Hindu Kush: Where Eurasian Sub-Continent Gene Flows Converge." PLoS ONE 8(10): e76748. doi:10.1371/journal.pone. ...
Davison A, Chiba S, Barton NH, Clarke B (2005). "Speciation and Gene Flow between Snails of Opposite Chirality". PLoS Biology. ... Mating and gene flow between mirror-image snails". Evolution Letters. 1 (6): 282-291. doi:10.1002/evl3.31. ISSN 2056-3744. ... Ueshima R. & Asami T. (16 October 2003). "Evolution: Single-gene speciation by left-right reversal". Nature 425: 679. doi: ... Richards, Paul M.; Morii, Yuta; Kimura, Kazuki; Hirano, Takahiro; Chiba, Satoshi; Davison, Angus (2017-12-01). "Single-gene ...
... in FGFR genes) and mutations that lead to loss of function (in TWIST genes).[38][39] Craniosynostosis is therefore likely the ... This can be further complicated with a possible Arnold-Chiari malformation, which can partially obstruct the flow of cerebro- ... Gene Loeys-Dietz syndrome wide-set eyes • split uvula or cleft palate • arterial tortuosity • aortic root dilatation • ... In terms of syndromic craniosynostosis not only do FGFR3 and TWIST genes feature, but also FGFR1 and in particular FGFR2, which ...
There are a number of rare cases of diabetes that arise due to an abnormality in a single gene (known as monogenic forms of ... and poor blood flow in the limbs which may lead to amputations.[1] The sudden onset of hyperosmolar hyperglycemic state may ... Most cases of diabetes involve many genes, with each being a small contributor to an increased probability of becoming a type 2 ... All of these genes together still only account for 10% of the total heritable component of the disease.[41] The TCF7L2 allele, ...
Berkowitz, S.A., Philo, J.S. Monitoring the Homogeneity of Adenovirus Preparations (a Gene Therapy Delivery System) Using ... ultracentrifuges can separate molecules in batch or continuous flow systems. ...
"Cross" (Eugene Novotney). The clave rhythm and clave concept have been used in some modern art music ("classical") compositions ... Clave has a natural flow with a certain tension and resolves points. I found if I kept these points in the new meters they ... Novotney, Eugene N. (1998) "Thesis: The 3:2 Relationship as the Foundation of Timelines in West African Musics" (registration ... Another clave-based composition that has "gone global" is the snare drum suite "Cross" by Eugene D. Novotney. ...
So sind neben einer speziellen Nahrung eine staubfreie Einstreu in möglichst keimfreier Umgebung (Laminar-Flow-Käfige), ... "Nude", a new hairless gene with pleiotropic effects in the mouse. In: Genet Res 8/1966, S. 295-309. PMID 5980117 ...
Kulikova, Irina V.; Zhuravlev, Yury N.; McCracken, Kevin G. (2004). "Asymmetric hybridization and sex-biased gene flow between ... as gene flow with other populations is very limited.[15]. Also, the paucity of morphological differences between the Old World ... The wild mallard is the ancestor of most domestic ducks, and its naturally evolved wild gene pool gets genetically polluted by ... Due to the variability of the mallard's genetic code, which gives it its vast interbreeding capability, mutations in the genes ...
feed(lactose):-make(permease),make(galactosidase). make(Enzyme):-code(Gene,Enzyme),express(Gene). express(lac(X)):-amount( ... Like all enzymes, these are made if they are coded by a gene (Gene) that is expressed (described by the second rule). The two ... in a cluster of genes (lac(X)) - called an operon - that is expressed when the amounts (amt) of glucose are low and lactose are ... enzymes of permease and galactosidase are coded by two genes, lac(y) and lac(z) respectively (stated in the fifth and sixth ...
eds.). Cochlear Blood Flow Changes With Short Sound Stimulation. Scientific basis of noise-induced hearing loss. New York ... Yamashita, D., Minami, S. B., Kanzaki, S., Ogawa, K., & Miller, J. M. (2008). Bcl-2 genes regulate noise-induced hearing loss. ...
The HLA genes fall in two categories (Type I and Type II). In general, mismatches of the Type-I genes (i.e. HLA-A, HLA-B, or ... Ursodiol has been shown to help prevent VOD, presumably by facilitating the flow of bile. ... as members of the same ethnic group are more likely to have matching genes, including the genes for HLA.[24] ... A mismatch of an HLA Type II gene (i.e. HLA-DR, or HLA-DQB1) increases the risk of graft-versus-host disease. In addition, a ...
"DNA Research: An International Journal for Rapid Publication of Reports on Genes and Genomes. 15 (4): 173-183. doi:10.1093/ ... "Weekend: Sake breweries go with the flow to survive". Retrieved December 29, 2009.. [dead link ...
First, the classic (rod or cone) photoreceptor is depolarized in the dark, which means many sodium ions are flowing into the ... NR2E3 further restricts cells to the rod fate by repressing cone genes. RORbeta is needed for both rod and cone development. ... CRX further defines the photoreceptor specific panel of genes being expressed. NRL expression leads to the rod fate. ... photoreceptor gene expression; and lastly axonal growth, synapse formation and outer segment growth. ...
Many modern molecular tests such as flow cytometry, polymerase chain reaction (PCR), immunohistochemistry, cytogenetics, gene ... Genetics is the study of genes, and their role in biological inheritance. ... blood flow, or other), and a radionuclide (usually either a gamma-emitter or a positron emitter). There is a degree of overlap ... as the causative genes of most monogenic genetic disorders have now been identified, and the development of techniques in ...
According to this model, new genes are created by non-adaptive processes, such as by random gene duplication. These novel ... All changes in the gene frequencies of populations--and quite often in the traits those genes influence--are by definition ... how new alternative spliced isoforms of genes arise, how gene scrambling in ciliates evolved, and how pervasive pan-RNA editing ... If this decay results in a situation where all of the genes are now required, the organism has been trapped in a new state ...
Tertiary gene pool: L. lamottei and L. tomentosus. Crosses generally fail between members of different gene pools. However, ... A combination of gravity, screens and air flow is used to clean and sort lentils based on shape and density. After destoning, ... According to their inter-crossability Lens species can be divided into three gene pools: *Primary gene pool: L. culinaris (and ... Even if crosses are successful, many undesired genes may be introduced as well in addition to the desired ones. This can be ...
Kopaliani, N.; Shakarashvili, M.; Gurielidze, Z.; Qurkhuli, T.; Tarkhnishvili, D. (2014). "Gene Flow between Wolf and Shepherd ... DNA analysis consistently shows that all existing red wolves carry coyote genes. This has caused a problem for Canid taxonomy, ... even if there is a low percentage of wolf genes in the hybrid.[11] States such as Indiana and Arkansas allow the ownership of ... it will appear more like a wolf than a husky because it contains more genes from the wolf.[11] This means that the appearance ...
Mutations and deletions of so-called tumor suppressor genes, such as P53, are thought to be the cause of some forms of brain ... caused by the blockage of the free flow of cerebrospinal fluid.[42] ... Experimental treatments include targeted therapy, gamma knife radiosurgery,[45] boron neutron capture therapy and gene therapy. ... "A uniquely stable replication-competent retrovirus vector achieves efficient gene delivery in vitro and in solid tumors". Human ...
Mallove, Eugene (1991), "Fire from Ice: Searching for the Truth Behind the Cold Fusion Furor", London: Wiley, ISBN 0-471-53139- ... Shanahan, Kirk L. (23 May 2002), "A systematic error in mass flow calorimetry demonstrated", Thermochimica Acta, 382 (2): 95- ...
The studies on fungal evolutionary genomics will further elucidate the earliest stages of divergence as a result of gene flow, ... Such a gene that exhibits multiple phenotypic expression is called a pleiotropic gene . Therefore mutation in a pleiotropic ... Gene pleiotropy occurs when a gene product interacts with multiple other proteins or catalyzes multiple reactions. ... Pleiotropy describes the genetic effect of a single gene on multiple phenotypic traits. The underlying mechanism is genes that ...
Flow-FISH[edit]. Flow-FISH uses flow cytometry to perform FISH automatically using per-cell fluorescence measurements. ... RNA probes can be designed for any gene or any sequence within a gene for visualization of mRNA,[3][4][5] lncRNA[6][7][8] and ... The technology has potential applications in cancer diagnosis,[14] neuroscience, gene expression analysis,[15] and companion ... MA-FISH is applied for detecting the HER2 gene in breast cancer tissues.[16] ...
Nora D Volkow; Joanna S Fowler; Gene-Jack Wang (2007). "The addicted human brain: insights from imaging studies". In Andrew R ... "Solving the hard problem of consciousness involves determining how physiological processes such as ions flowing across the ... Dawkins, R. (1976) The Selfish Gene. Oxford: Oxford University Press. ISBN 88-04-39318-1 ... genes, and evolutionary histories.[160][161][162] This point of view raises the fear that such attribution makes it impossible ...
Typical flow rates, dew point, and residual radon concentration are 18 m3/h, −65 °C (@+1 kg/cm2), and a few mBq m−3, ... Charles Kane and Eugene Mele (2019). Life sciences. *Cornelia Bargmann, David Botstein, Lewis C. Cantley, Hans Clevers, Titia ... Data flow from online system is 450 kbytes s−1 on average, corresponding to 40 Gbytes day−1 or 14 Tbytes yr−1. Magnetic tapes ... air flows out the tunnel, drawing radon-rich air from deep within the mine past the experimental area.[7] ...
So a myocardial infarction or heart attack is when blood flow to part of the heart stops. Then that part of the heart dies. ... Genetics (whether people have good genes or bad ones from their parents.) ... When atherosclerosis gets bad enough, it can cause blockage of blood flow in arteries. This can hurt whatever the artery brings ... If it is hurt from low blood flow, but not enough to die, it is called ischemia. ...
Upon his election, Cardinal Eugene Tisserant asked him the ritual questions of whether he would accept and if so, what name he ... and the lack of air flow in his sealed triple coffin rather than a miracle. When John XXIII's body was moved in 2001, the ...
2005). Bioinformatics: A Practical Guide to the Analysis of Genes and Proteins (en inglés) (third edition ed.). Wiley. ISBN 0- ... "New Assessment of Endothelium-Dependent Flow-Mediated Vasodilation to Characterize Endothelium Dysfunction". American Journal ... 1993) A Hidden Markov Model that finds genes in E. coli DNA ... Serial Analysis of Gene Expression, Análise en serie da ... Circular SV40 DNA Molecules Containing Lambda Phage Genes and the Galactose Operon of Escherichia coli" (PDF). Proceedings of ...
Fabian, Gene L.; O'Donnell, Richard H.; Tom, Joe G.; Malone, Philip G. (1996). Use of Shock-Absorbing Concrete (SACON) as an ... The foam enables the slurry to flow freely due to the thixotropic behaviour of the foam bubbles, allowing it to be easily ...
Some degree of gene flow is normal, and preserves constellations of genes and genotypes.[118][119] An example of this is the ... Hybrids resulting from invasive species interbreeding with native species can incorporate their genotypes into the gene pool ...
Mutation in the CACNA1C gene, the single-nucleotide polymorphism located in the third intron of the Cav1.2 gene,[18] are ... When depolarization occurs, calcium ions flow through the channel and some bind to Calmodulin. The Calcium/Calmodulin binding ... "Entrez Gene: voltage-dependent, L type, alpha 1C subunit".. *^ Narayanan D, Xi Q, Pfeffer LM, Jaggar JH (Sep 2010). " ... Gene ontology. Molecular function. • calcium channel activity. • metal ion binding. • voltage-gated ion channel activity. • ion ...
They found that as these chills increase, many changes in cerebral blood flow are seen in brain regions such as the amygdala, ... Peretz, Isabelle (2008). "Musical Disorders: From Behavior to Genes". Current Directions in Psychological Science. 17 (5): 329- ... A PET study conducted by Zatorre, Halpern, Perry, Meyer and Evans (1996) investigated cerebral blood flow (CBF) changes related ... used PET to measure changes in cerebral blood flow while participants listened to music that they knew to give them the "chills ...
"Sex-biased gene flow in African Americans but not in American Caucasians", GMR, 2007, Vol. 12, No. 6. ...
... is used as a rather conservative flow tracer in hydrological tracer tests to help in understanding of water flow of ... The latter is a common alternative to digoxigenin, and the two are used together for labelling two genes in one sample.[3] ... Fluorescein has often been used to track water movement in groundwater to study water flow and observe areas of contamination ... flow cytometry). Additional biologically active molecules (such as antibodies) may also be attached to fluorescein, allowing ...
Sex-biased dispersal and spatial heterogeneity affect landscape resistance to gene flow in fisher. Publications Posted on: June ... Gene flow is an evolutionary process that supports genetic connectivity and contributes to the capacity of species to adapt to ... Quantifying functional connectivity: The role of breeding habitat, abundance, and landscape features on range-wide gene flow in ... how differences between two empirical resistance models for the same geographic area affected predictions of gene flow ...
This explain why genes on the Z chromosome cannot flow from the medium ground finch to the cactus finch via these hybrid ... "Female-biased gene flow between two species of Darwins finches," by Sangeet Lamichhaney, Fan Han, Matthew T. Webster, B. ... Because these hybrid females receive their single Z chromosome from their cactus finch father there is no gene flow on Z ... Gene flow between species influences evolution in Darwins finches The Office of Communications ...
ERC grant 310763: GeneFlow The goal of the project is to investigate the importance of nuclear gene flow between populations ... It is not yet clear whether this discrepancy is due to incomplete lineage sorting or massive male-mediated gene flow. We also ... cave hyenas and wolves to investigate which role nuclear gene flow played in the evolutionary history of these species.. ... de/ibb-genomics/research/erc-gene-flow.html ...
Still, male-mediated gene flow might occur through rare events such as extra-group matings leading to extra-group paternity ( ... However, gene flow mediated by apparently philopatric sex may still occur and potentially alters population structure. In our ... In bonobos more data are needed to refine the estimated rate of gene flow. Our findings suggest that dispersal patterns in ... Conclusions/Significance The similarity of inferred rates of male-mediated gene flow and published rates of EGP in western ...
... because there is little to no gene flow to provide recombination of the gene pools. Barriers to gene flow need not always be ... There are a number of factors that affect the rate of gene flow between different populations. Gene flow is expected to be ... For this reason,gene flow has been thought to constrain speciation by combining the gene pools of the groups, and thus, ... Human-mediate gene flow: The captive genetic management of threatened species is one way in which humans attempt to induce gene ...
A model of the effect of gene flow and natural selection in a continuously distributed, infinite population is developed. ... 3) A geographic barrier to dispersal causes a drastic change in the gene frequencies at the barrier only when almost all of the ... The results are: (1) there is a characteristic length scale of variation of gene frequencies, (see PDF). The population cannot ... 2) The reduction in the fitness of the heterozygote causes a cline in gene frequencies to become steeper. ( ...
... and genomic data shows that the reduction of gene flow for Z-linked loci primarily reflects female-biased gene flow, arising ... the authors show that gene exchange between the two species is asymmetric and female biased. ... and genomic data shows that the reduction of gene flow for Z-linked loci primarily reflects female-biased gene flow, arising ... Female-biased gene flow between two species of Darwins finches. *Sangeet Lamichhaney ORCID: orcid.org/0000-0003-4826-03491. ...
While it is poetic to think of genes as flowing among populations, ebbing and flowing from the source to the fringes, there are ... A very recent paper by Sexton and colleagues discusses how nuanced gene flow can be. The result was elegant, yet has profound ... Sexton JP, Strauss SY, & Rice KJ (2011). Gene flow increases fitness at the warm edge of a species range. Proceedings of the ... Nevertheless, measuring the flow of genes among populations remains a powerful inferential tool in ecology. ...
Research also found that a demographic model that estimates gene flow from these early modern humans into the ancestors of the ... Altai Neanderthal shows gene flow from early modern humans. Chinese Academy of Sciences Headquarters ... The individual shows signs of gene flow from modern humans. In comparison, the two Neanderthals from European caves who were ... This introgression is much earlier than previously reported gene flow from Neanderthals into modern humans outside Africa ( ...
Study Reveals Surprising Amount of Gene Flow Among Butterfly Species. Many butterfly species show a high amount of gene flow ... show a surprisingly high amount of gene flow among them, said James Mallet of Harvard University, the senior author of the ... For Mallet and colleagues, understanding how butterflies pass genes back and forth -- a process known as introgression -- began ...
Theory predicts that gene flow hinders local adaptation, unless it is coupled with habitat choice. Here, the authors show that ... Our study challenges the idea that high gene flow precludes local adaptation, and provides unique experimental evidence of ... Local adaptation is assumed to occur under limited gene flow. However, habitat-matching theory predicts dispersal should favour ... Gene flow favours local adaptation under habitat choice in ciliate microcosms. *Staffan Jacob. 1,2. , ...
Instead, Indias gene diversity was connected more to language. Indians who spoke the same language were more closely related, ... A new study looked at gene distribution among Indian populations. It found that, unlike European genetic distribution, Indian ... Study: Language (not geography) major force behind Indias gene flow The study found that people who spoke the same language ... None of this is to say that geography played no part in the ancestral gene flow of India, nor that social and cultural factors ...
... but there has been no estimate of the exact proportion of this gene flow, or of its date. Here, we apply genomic methods to ... Gene flow Is the Subject Area "Gene flow" applicable to this article? Yes. No. ... a continuous gene flow model and found that the estimated dates are intermediate between the start and end of the gene flow, as ... rather than the single pulse of gene exchange that we modeled. To explore this, we first simulated two distinct gene flow ...
Gene flow in complex landscapes: Testing multiple hypotheses with causal modeling. *Multiple-scale prediction of forest loss ... In this black bear population, gene flow is facilitated by contiguous forest cover at middle elevations.. Publication Notes. * ... Gene flow in complex landscapes: Testing multiple hypotheses with causal modeling. American Naturalist 168(4): 486-499.. ...
Estimating Barriers to Gene Flow from Distorted Isolation-by-Distance Patterns. View ORCID ProfileHarald Ringbauer, Alexander ... Estimating Barriers to Gene Flow from Distorted Isolation-by-Distance Patterns. View ORCID ProfileHarald Ringbauer, Alexander ... Estimating Barriers to Gene Flow from Distorted Isolation-by-Distance Patterns. View ORCID ProfileHarald Ringbauer, Alexander ... Estimating Barriers to Gene Flow from Distorted Isolation-by-Distance Patterns Message Subject (Your Name) has forwarded a page ...
... and how restricted gene flow can lead to the formation of new species. Video by California Academy of Sciences. ... What happens if gene flow is slowed down or somehow prevented? Imagine a population in which sexual reproduction and variation ... Therefore, we now have what is called a restriction of gene flow between the two separated groups. What had once been a single ... This mixing of genetic information among interbreeding members of a population or species is known as gene flow. It maintains ...
... these results support the hypothesis that Sub-Saharan gene flow detected in Europe entered with North African gene flow. We ... Southern Europe has higher North African gene flow. Laura R. Botigué, Brenna M. Henn, Simon Gravel, Brian K. Maples, ... Southern Europe has higher North African gene flow. Laura R. Botigué, Brenna M. Henn, Simon Gravel, Brian K. Maples, ... A model of gene flow from the Near East into both Europe and North Africa, such as a strong demic wave during the Neolithic, ...
Pollen and gene flow in fragmented habitats. Authors. *. Manja M. Kwak,. Corresponding author. *Laboratory of Plant Ecology and ... Shenhua Qian, Waka Saito, Makiko Mimura, Shingo Kaneko, Yuji Isagi, Eri Mizumachi, Akira S. Mori, Asymmetric gene flow and the ... In the absence of stepping stones even short distances between populations act as strong barriers for gene flow. ... and Urbanization on Seed Production and Gene Flow in an Endangered Maple (Acer miyabei), The American Midland Naturalist, 2014 ...
... and phylogenies from the inteins recovered to explore how intein distribution can provide insight on the dynamics of gene flow ... and phylogenies from the inteins recovered to explore how intein distribution can provide insight on the dynamics of gene flow ... to infer patterns of gene transfer within the Halobacteria. We surveyed one hundred and eighteen genomes representing twenty- ... the consensus phylogenetic signal derived from intein sequences is compatible with vertical inheritance or with a strong gene ...
The speciation-with-gene-flow model posits that the genome is semi-permeable and hybridization may be a phase in the process of ... Assessment of gene flow across a hybrid zone in red-tailed chipmunks (Tamias ruficaudus).. Hird S1, Sullivan J. ... Using multilocus genotype data from the southern, older contact zone, we demonstrate that neutral gene flow is unusually low ... hybridization is the cause of mtDNA/morphology incongruence because there are non-zero levels of migration and gene flow. ...
Sandra A. Owusu, Alexis R. Sullivan, Jaime A. Weber, Andrew L. Hipp, and Oliver Gailing "Taxonomic Relationships and Gene Flow ... HYBRID BRIDGES TO GENE FLOW A CASE STUDY IN... Comparative Genomic and Population Genetic Analyses Indicate Highly Porous ... Taxonomic Relationships and Gene Flow in Four North American Quercus Species (Quercus section Lobatae). ... Sandra A. Owusu, Alexis R. Sullivan, Jaime A. Weber, Andrew L. Hipp, Oliver Gailing "Taxonomic Relationships and Gene Flow in ...
Plant DNA barcodes and the influence of gene flow. Authors. *. YAMAMA NACIRI,. * Unité de Phylogénie et de Génétique ... We show that the genome experiencing the highest gene flow is, in the majority of the cases, the best suited for species ... In this study, we confirm the theoretical prediction that gene flow influences species assignment with simulations and a ...
Julianno B. M. Sambatti and Kevin J. Rice "LOCAL ADAPTATION, PATTERNS OF SELECTION, AND GENE FLOW IN THE CALIFORNIAN SERPENTINE ... Local adaptation to riparian and serpentine habitats was studied in Helianthus exilis along with an analysis of gene flow ... Whether a species evolves as a cohesive unit depends critically on the dynamic balance between homogenizing gene flow among ... Julianno B. M. Sambatti, Kevin J. Rice "LOCAL ADAPTATION, PATTERNS OF SELECTION, AND GENE FLOW IN THE CALIFORNIAN SERPENTINE ...
In the various embodiments, the present invention provides controlled and uniform mixing of gene therapy vectors and gene ... The invention relates generally to methods and apparatuses that are adapted for the preparation of gene therapeutic ... Concurrent flow mixing methods and apparatuses for the preparation of gene therapy vectors and compositions prepared thereby. ... Gene Therapy Vectors. Any number of known gene therapy vectors may be utilized within the context of the present invention. ...
... karyotypes were flow-sorted and the DNA was used for the physical localization of seed storage and nonstorage (USP) protein ... vicilin genes, legumin B3 genes), III (legumin B4 genes), IV (pseudogenes ψ1) and V (legumin A genes and pseudogenes ψ1). ... Vicia faba chromosome flow sorting gene mapping PCR seed protein genes This is a preview of subscription content, log in to ... Cotter F, Nasipuri S, Lam G, Young BD (1989) Gene mapping by enzymatic amplification from flow-sorted chromosomes.Genomics 5: ...
In population genetics, gene flow (also known as gene migration or allele flow) is the transfer of genetic variation from one ... Unless indicated otherwise, the text in this article is either based on Wikipedia article "Gene flow" or another language ... If the rate of gene flow is high enough, then two populations are considered to have equivalent allele frequencies and ...
Those with the gene variation are three times more likely to experience dangerous decreases in blood flow to the heart - a ... Mental stress reduces blood flow to the heart in patients with gene variation. 17.04.2008 ... "Searching for the presence of this gene may be one way to better identify patients who are at an increased risk for the ... Images were taken of blood flow to the heart at rest and during the speech task. Blood samples also were collected and analyzed ...
As winter turns to spring, the McKenzie River flows toward Eugene with impressive force. While powerful, the river is not ... OSU Study Looks at McKenzie Flows. News by Amy KlarupPosted on 02/28/2013. *Click to share on Facebook (Opens in new window) ... Eugenes Arcimoto is once again making big moves in the delivery world. The three-wheel electric car maker is finding a way to ... Eugenes Arcimoto makes huge deal with DHL. BlogNews 10 hours ago. ...
Gene Flow: Two-Population Dynamics. Adjust m1, m2, s1, and s2 to the right: ... Gene Flow: Two-Population Dynamics. When populations of the same species are separated geographically, genetic drift and ... For this reason, gene flow is said to be the great homoginizing agent. ...
Pancreas cancer liquid biopsy flows from blood-borne packets of tumor genes. University of Texas M. D. Anderson Cancer Center ... Pancreas cancer liquid biopsy flows from blood-borne packets of tumor genes MD Anderson scientists do next-generation analysis ... Analyzing gene expression. "Full RNA sequencing is important because genome sequencing tells you what genes are altered, while ... The team conducted whole genome, whole exome and gene expression analysis of tumors in three patients using DNA and RNA found ...
  • The goal of the project is to investigate the importance of nuclear gene flow between populations for the evolution of Pleistocene mammalian species. (uni-potsdam.de)
  • If the rate of gene flow is high enough, then two populations are considered to have equivalent genetic diversity and therefore effectively a single population. (wikipedia.org)
  • Gene flow is an important mechanism for transferring genetic diversity among populations. (wikipedia.org)
  • Migrants into or out of a population may result in a change in allele frequencies (the proportion of members carrying a particular variant of a gene), changing the distribution of genetic diversity within the populations. (wikipedia.org)
  • There are a number of factors that affect the rate of gene flow between different populations. (wikipedia.org)
  • Gene flow is expected to be lower in species that have low dispersal or mobility, occur in fragmented habitats, there is long distant between populations, and smaller populations sizes. (wikipedia.org)
  • As dispersal distance decreases, gene flow is impeded and inbreeding, measured by the inbreeding coefficient (F), increases.For example, many island populations have low rates of gene flow due to geographically isolated and small population size. (wikipedia.org)
  • When gene flow is blocked by physical barriers, this results in Allopatric speciation or a geographical isolation that does not allow populations of the same species to exchange genetic material. (wikipedia.org)
  • In some cases, they can be artificial, man-made barriers, such as the Great Wall of China, which has hindered the gene flow of native plant populations. (wikipedia.org)
  • Analyzing fragments of conserved gene sequences can give us a deeper picture of how populations were historically connected and a more conservative definition of populations. (scientificamerican.com)
  • Using SNP data from 2,099 individuals in 43 populations, we show that estimates of recent shared ancestry between Europe and Africa are substantially increased when gene flow from North Africans, rather than Sub-Saharan Africans, is considered. (pnas.org)
  • In the absence of stepping stones even short distances between populations act as strong barriers for gene flow. (wiley.com)
  • Whether a species evolves as a cohesive unit depends critically on the dynamic balance between homogenizing gene flow among populations and potentially disruptive local adaptation. (bioone.org)
  • To examine this evolutionary balance between "global" gene flow and local selection, we studied northern Californian populations of Helianthus exilis , the serpentine sunflower, within a mosaic of contrasting serpentine and nonserpentine areas that differ considerably in soil chemistry and water availability. (bioone.org)
  • Local adaptation to riparian and serpentine habitats was studied in Helianthus exilis along with an analysis of gene flow patterns among populations within these habitats. (bioone.org)
  • ii) We evaluate the impact of cytoplasmic incompatibility on gene flow between populations by calculating effective migration rates. (hu-berlin.de)
  • Effects of polyploidisation on gene flow between natural populations are little known. (uio.no)
  • Central European diploid and tetraploid populations of Arabidopsis arenosa and A. lyrata are here used to study interspecific and interploidal gene flow, using a combination of nuclear and plastid markers. (uio.no)
  • Our results emphasize the need to understand the behaviour of migrants and the extent to which they contribute offspring in order to determine whether dispersal results in gene flow and prevents declines in resident populations. (usda.gov)
  • Green and colleagues [4] tested explicitly for this kind of gene flow, from "modern" into Neandertal populations and found none. (blogspot.com)
  • They illustrate the important role of gene flow among populations and its potential consequences. (science20.com)
  • So how much gene flow is there between plant populations? (science20.com)
  • Although it was first seen in the 1940s to be the evolutionary glue that held species together, and thus a significant evolutionary force, a few decades later when quantitative data on gene flow in plant populations began being collected, this view changed as evidence seemed to indicate that gene flow was not all that significant. (science20.com)
  • Not only was intra-specific gene flow among populations seen to be minimal at that time, but, somewhat incongruously, inter-specific hybridization, or the movement of genes among species, was seen to be a much larger force in evolution than intra-specific allele movement. (science20.com)
  • As it turns out, despite the initial skepticism about the importance of gene flow, modern empirical and theoretical research using up-to-date molecular and DNA techniques have shown us not only how surprisingly far the flow of genes between distant plant populations can be, but also that the flow of alleles among populations is just as important, if not more so in some cases, as natural selection. (science20.com)
  • Indeed, even just a low level of gene flow between populations can counter opposing forces of mutation, genetic drift, and selection. (science20.com)
  • MIT researchers have developed a gene flow measurement that defines ecologically important populations of microbes. (mit.edu)
  • Now, MIT researchers have developed a simple measurement of gene flow that can define ecologically important populations among bacteria and archaea, including pinpointing populations associated with human diseases. (mit.edu)
  • Led by microbiology graduate student Philip Arevalo, the researchers developed a metric of gene flow that they called PopCOGenT (Populations as Clusters Of Gene Transfer). (mit.edu)
  • This gene flow measurement can define distinct microbial populations, as the researchers discovered in their tests of three different kinds of bacteria. (mit.edu)
  • In Vibrio bacteria, for instance, closely related populations may share some core gene sequences, but they appear completely isolated from each other when viewed through this measurement of recent gene flow, Polz and colleagues found. (mit.edu)
  • One is the assumption that island-associated populations of dolphins have no restrictions on dispersal and gene flow. (epa.gov)
  • Another problem my research addresses is our inability to predict dispersal and gene flow among island-associated dolphin populations, particularly those that are elusive, threatened, or endangered. (epa.gov)
  • Furthermore, SSRs can be used to advance knowledge of gene flow in natural populations. (oregonstate.edu)
  • Comparisons between sympatric and allopatric populations of H. melpomene, H. cydno, and H. timareta revealed a genome-wide trend of increased shared variation in sympatry, indicative of pervasive interspecific gene flow. (ku.edu)
  • In many marine fish species, genetic population structure is typically weak because populations are large, evolutionarily young and have a high potential for gene flow. (diva-portal.org)
  • We applied Bayesian and coalescent-based analyses to estimate contemporary and historical gene flow among these populations and to infer their evolutionary history. (royalsocietypublishing.org)
  • These four populations have been in migration-drift equilibrium maintained by high gene flow. (royalsocietypublishing.org)
  • We found the highest rates of contemporary gene flow in populations that are connected by forest corridors. (royalsocietypublishing.org)
  • Identifying currents in the gene pool for bacterial populations using an integrative approach. (nih.gov)
  • Gene flow network identified in the N. meningitidis and N. lactamica populations.To investigate the ancestral admixture of a certain population, one can look at all the arrows pointing at this population. (nih.gov)
  • A typical population contains the major sources of its own, denoted as a self-looping arrows, and small proportions of gene flow from other populations. (nih.gov)
  • For instance, population 29 has 73% of its own genetic makeup and 27% of the DNA introduced via gene flow from other populations. (nih.gov)
  • It can be seen from the grey box highlighted in Figure 7 that two admixture arrows that imply inter-species gene flow remain significant, where two of the N. meningitidis populations (11 and 19) are constantly influencing the genetic makeup of one population of N. lactamica (population 29). (nih.gov)
  • Interspecific gene flow can lead to the formation of hybrid populations that have a competitive advantage over the parental populations, even for hybrids from a cross between crops and wild relatives. (wur.nl)
  • Subsequent high rates of gene flow have served to homogenize the majority of the genome between populations on and off the Sand Hills, with the exception of the Agouti pigmentation locus. (ovid.com)
  • The effects of gene flow and population isolation on the genetic structure of␣reintroduced wild turkey populations: Are genetic signatures of source populations retained? (springer.com)
  • In reintroduced populations connected by gene flow, patterns of genetic structure initiated by the founding event may become obscured, and populations may eventually follow an isolation-by-distance model of genetic differentiation. (springer.com)
  • Taking advantage of well-documented reintroduction histories of wild turkey populations in Indiana, we assessed the degree to which gene flow among reintroduced populations has obscured genetic signatures left by the founding events. (springer.com)
  • Although we found some case-specific evidence for gene flow, particularly in regions where populations are in close proximity, our data indicate on overall paucity of gene flow at a regional scale. (springer.com)
  • Allendorf FW (1983) Isolation, gene flow, and genetic differentiation among populations. (springer.com)
  • If there is no gene flow between populations that were isolated from each other in some way, then one could conclude that speciation had occurred because members of the two populations were not interbreeding. (wyzant.com)
  • If there is a high rate of gene flow between two populations, then speciation will occur at a very low rate because a significant amount of genetic material is being exchanged between the two populations. (wyzant.com)
  • Conversely, if there is a low rate of gene flow between two populations, it is likely that speciation would occur at a much faster rate because those two populations would be more isolated from each other and less exchange of genetic material would occur. (wyzant.com)
  • In addition, we inferred positive population growth for most populations and detected evidence of historical gene flow between populations that are now physically isolated. (datadryad.org)
  • The results provided genetic evidence that gene flow between Jewish and non-Jewish populations occurred early in Jewish settlement in Europe with isolation of the groups thereafter. (jogg.info)
  • Analyses of autosomal genes, reflecting a combination of paternal and maternal inheritance, have indicated a significant degree of European admixture among Ashkenazi Jews as well as a close relationship between most contemporary Jews and non-Jewish populations from the Levant (Atzmon et al. (jogg.info)
  • However, a different, also justifiable mutation rate suggested the origin was much more recent, implicating geneflow in Europe after the split as the source as of the mutation common to both Sephardic and Ashkenazi populations. (jogg.info)
  • Population structure, diversity and gene flow in four populations of Aciphylla glaucescens were studied using allozymes. (newzealandecology.org)
  • Boutilier, R. G. 1995-01-01 00:00:00 G. H. Pogson, K. A. Mesa and R. G. Boutilier Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, England High levels of gene flow have been implicated in producing uniform patterns of allozyme variation among populations of many marine fish species. (deepdyve.com)
  • The discrepancy between gene flow estimates, combined with the observation of a large excess of rare RFLP alleles, suggests that the Atlantic cod has undergone a recent expansion in population size and that populations are significantly displaced from equilibrium. (deepdyve.com)
  • Because gene flow is a process that affects all loci equally, the heterogeneity observed among populations at the DNA level eliminates gene flow as the explanation for the homogeneous allozyme patterns. (deepdyve.com)
  • Altogether, our results highlight the importance of gene flow as a significant evolutionary force in shaping genetic patterns in the wild, and as a crucial process for the maintenance of genetic diversity in small populations. (uzh.ch)
  • The significant result shown by gene flow and genetic differentiation analyses as well as test of neutrality among the populations should have brought a clearer picture to the dynamics and distribution of Giardia infection. (biomedcentral.com)
  • Their population genetics were analyzed on many samples gathered from all over the tropics and subtropics to know their differentiation process into species and rates of gene flows between populations to keep the species. (nii.ac.jp)
  • These results suggested substantial gene flow occurred between populations in the different oceanic regions due to sea-drifted seeds. (nii.ac.jp)
  • A strong genetic difference b … More etween the Pacific and Atlantic populations of H.pernambucensis was observed, which indicates that gene flow in this species between the two regions has been prevented. (nii.ac.jp)
  • Moreover gene flows among distant populations were observed. (nii.ac.jp)
  • In the Western United States , phrynosomatine lizards have a complex history coupled to geologic and climatic changes from mountain uplift to glaciation events that have restricted or eliminated gene flow between populations of horned lizards . (ccsu.edu)
  • This study examined populations of P . hernandesi , P . douglasi and P . ditmarsi , for patterns of gene flow with a particular focus on the Madrean archipelago populations of P . hernandesi due to their restriction to the relictual high-elevation mesic habitats . (ccsu.edu)
  • Populations are often exposed to multiple sources of gene flow, but accounts are lacking of the population genetic dynamics that result from these interactions or their effects on local evolution. (gc.ca)
  • Our results point to potentially complex evolutionary outcomes for populations experiencing multiple sources of gene flow. (gc.ca)
  • Despite the traditional view that species do not exchange genes by hybridization, a new study led by Princeton ecologists Peter and Rosemary Grant show that gene flow between closely related species is more common than previously thought. (princeton.edu)
  • A team of scientists from Princeton University and Uppsala University detail their findings of how gene flow between two species of Darwin's finches has affected their beak morphology in the May 4 issue of the journal Nature Ecology and Evolution. (princeton.edu)
  • Because these hybrid females receive their single Z chromosome from their cactus finch father there is no gene flow on Z chromosomes between species through these hybrid females. (princeton.edu)
  • We wondered whether this evolutionary change could be explained by gene flow between the two species. (princeton.edu)
  • We are now applying the technical approaches developed in our work on cave and brown bears to further samples from these species as well as to mammoths, cave hyenas and wolves to investigate which role nuclear gene flow played in the evolutionary history of these species. (uni-potsdam.de)
  • Immigration may also result in the addition of new genetic variants to the established gene pool of a particular species or population. (wikipedia.org)
  • Samples of the same species which grow on either side have been shown to have developed genetic differences, because there is little to no gene flow to provide recombination of the gene pools. (wikipedia.org)
  • For example, two palm species of Howea found on Lord Howe Island were found to have substantially different flowering times correlated with soil preference, resulting in a reproductive barrier inhibiting gene flow. (wikipedia.org)
  • Many butterfly species show a high amount of gene flow between them. (nsf.gov)
  • An analysis of 20 butterfly genomes found evidence that many butterfly species -- including distantly related ones -- show a surprisingly high amount of gene flow among them, said James Mallet of Harvard University , the senior author of the study. (nsf.gov)
  • For Mallet and colleagues, understanding how butterflies pass genes back and forth -- a process known as introgression -- began with the creation of 20 new "genome assemblies" of various species. (nsf.gov)
  • Scientists studying genes know that changes of various types happen in the genetic code itself, which introduces variations among individuals and among species. (khanacademy.org)
  • In this study, we confirm the theoretical prediction that gene flow influences species assignment with simulations and a literature survey. (wiley.com)
  • We show that the genome experiencing the highest gene flow is, in the majority of the cases, the best suited for species delimitation. (wiley.com)
  • The traditional view of the species as the fundamental unit of evolution has been challenged by observations that in heterogeneous environments, gene flow may be too restricted to overcome the effects of local selection. (bioone.org)
  • Gene flow has been recognized as a significant evolutionary force since the 1940s but its relative role in maintaining a species' genetic integrity and/or its diversity has been debated. (science20.com)
  • How important is gene flow for maintaining a species' identity and diversity, and what are the implications of these processes for evolution, conservation of endangered species, invasiveness, or unintentional gene flow from domesticated crops to wild relatives? (science20.com)
  • Hybrids between wild and cultivated species were formed in some species of Cucurbitaceae indicating a higher possibility of gene flow. (lu.se)
  • As a result, members of a species share a set of genes that differs from other species. (mit.edu)
  • Most speciation events probably occur gradually, without complete and immediate reproductive isolation, but the full extent of gene flow between diverging species has rarely been characterized on a genome-wide scale. (ku.edu)
  • Our results show that the loci influenced by selection can serve as powerful markers for detecting population structure in high gene-flow marine fish species. (diva-portal.org)
  • Understanding the patterns of gene flow of an endangered species metapopulation occupying a fragmented habitat is crucial for landscape-level conservation planning and devising effective conservation strategies. (royalsocietypublishing.org)
  • Dispersal and gene flow in a metapopulation maintain local demographic and genetic variation, and increase the probability of species persistence [ 1 - 3 ]. (royalsocietypublishing.org)
  • Functionality of structural corridors can be ascertained by examining the behavioural response of the individuals of a species and facilitation of their ecological processes such as movement, dispersal and gene flow through them [ 11 - 12 ]. (royalsocietypublishing.org)
  • Very few empirical studies have estimated gene flow in cat species [ 13 - 16 ] and none, to our knowledge, has investigated historical gene flow. (royalsocietypublishing.org)
  • Such a result should have been precluded by the expected divergence between the species unless there has been interspecies gene flow. (deepdyve.com)
  • Thus, in addition to the previously reported presence of small amounts of Mus spretus-specific repetitive DNA in M. m. domesticus, there is a detectable flow of unique sequence between the two species. (deepdyve.com)
  • To assess the role of drive during speciation, we combine high-resolution genetic mapping of X-linked hybrid male sterility with population genomics analyses of divergence and recent gene flow between the fruitfly species, Drosophila mauritiana and D. simulans. (unl.edu)
  • Gene diversity for Aciphylla glaucescens (H-e = 0.258) was greater at the species level compared with other outcrossing, wind pollinated plant species (H-e = 0.162). (newzealandecology.org)
  • To continue to add to our knowledge of how speciation occurs and how species interact, it is crucial to determine 1) how different categories of genes evolve as species diverge, 2) what happens to hybrids of two species, and 3) if genetic exchange is allowed between species, where it is located. (uiowa.edu)
  • In the first research aim of my dissertation, I look for population genetic trends and signatures of gene flow in a minimally studied set of Drosophila sister species using sequences of 26 nuclear and mitochondrial regions in 29 isofemale lines of D. subobscura and D. madierensis. (uiowa.edu)
  • We also find evidence of genetic exchange for some autosomal genes while both the sex chromosomes and mitochondrial genomes remain distinct between species. (uiowa.edu)
  • Over time, genomes of different species become more distinct, particularly the X chromosome and genes expressed higher in one sex. (uiowa.edu)
  • Molecular phylogenetic geography of pan tropic sea dispersed plants : Gene flow and species differentiation through geographic barrier. (nii.ac.jp)
  • Ecological divergence in the presence of gene flow in two closely related Oryza species (Oryza rufipogon and O. nivara). (semanticscholar.org)
  • Widespread and Adaptive Alterations in Genome-Wide Gene Expression Associated with Ecological Divergence of Two Oryza Species. (semanticscholar.org)
  • This research confirms the existence of potentially complex evolutionary processes when the population of a given species is exposed to multiple sources of gene flow. (gc.ca)
  • The coexistence of divergent groEL/cpn60 genes in different genomes in one cell offers insights into gene transfer from evolving chloroplasts to cell nuclei and convergent gene evolution in chlorophyll a/b versus chlorophyll a/c/phycobilin eukaryotic lineages. (nih.gov)
  • Targeted at beginners as well as experienced users, this handy reference explains the benefits and uses of flow cytometery in the study of plants and their genomes. (wiley.com)
  • He has constantly been developing novel techniques to study plant genomes, among them many methods based on flow cytometry. (wiley.com)
  • PopCOGenT measures recent gene flow or gene transfer between closely related genomes. (mit.edu)
  • I am using genetic and photo-identification techniques to explore dispersal and gene flow of spotted dolphins ( Stenella attenuata ) near the main Hawaiian Islands. (epa.gov)
  • 2. However, the temporal configuration of suitable habitat may also influence dispersal and gene flow in fragmented landscapes. (nerc.ac.uk)
  • Ploidal levels were confirmed by flow cytometry. (uio.no)
  • He has pioneered the use of flow cytometry in plant science for the analysis of nuclear genome size and regularly holds international training courses on the subject. (wiley.com)
  • Jan Suda heads the laboratory of flow and image cytometry at the Czech Academy of Sciences' Institute of Botany. (wiley.com)
  • The analysis of filamentous fungi by flow cytometry has been impossible to date due to their filamentous nature and size. (g3journal.org)
  • In this work, we have developed a method that combines single-spore microencapsulation and large-particle flow cytometry as a powerful alternative for the genetic analysis of filamentous fungi. (g3journal.org)
  • Growth could be monitored by light or fluorescent microscopy and Complex Object Parametric Analyzer and Sorter large-particle flow cytometry. (g3journal.org)
  • These drawbacks of filamentous fungal research can be solved, at least partially, with the use of high-throughput methods like, for instance, the combination of flow cytometry and sorting. (g3journal.org)
  • Carling, M. D., Lovette, I. J. & Brumfield, R. T. Historical divergence and gene flow: coalescent analyses of mitochondrial, autosomal and sex-linked loci in Passerina buntings. (nature.com)
  • Isolation with migration analyses suggested interspecific introgression from tetraploid A. arenosa to tetraploid A. lyrata and vice versa, and some interploidal gene flow, which was unidirectional from diploid to tetraploid in A. arenosa and bidirectional in A. lyrata. (uio.no)
  • We compared the spatial and temporal patterns of divergence and statistical power of three traditional genetic marker types, microsatellites, allozymes and mitochondrial DNA, with one microsatellite locus, Cpa112 , previously shown to be influenced by divergent selection associated with salinity, and one locus located in the major histocompatibility complex class IIA ( MHC-IIA ) gene, using the same individuals across analyses. (diva-portal.org)
  • The tpi sequences together with sequences from the global data obtained from the NCBI GenBank were used for genetic diversity analyses including identification of haplotypes, haplotype diversity, nucleotide diversity, Tajima's D and Fu and Li's D, gene flow and genetic differentiation tests. (biomedcentral.com)
  • To further investigate this differentiation, we carried out haplotype analyses, which provided partial evidence that sub-Saharan gene flow was higher towards North Africa than South Europe. (biomedcentral.com)
  • High rates of gene flow can reduce the genetic differentiation between the two groups, increasing homogeneity. (wikipedia.org)
  • We also found weak isolation-by-distance, lower among than within cropping region population differentiation, concordant moving directions of potato products and net gene flow and the highest gene diversity in the region with the most potato imports. (frontiersin.org)
  • Due to female philopatry, mtDNA provides a highly structured estimate of population differentiation, while male-biased gene flow is a homogenizing force for nuclear genetic variation. (datadryad.org)
  • As there is no consensus between the two genomic regions regarding gene flow through the Sahara, it is hard to reach a solid conclusion about its role in the differentiation between the two Mediterranean shores and more data are necessary to reach a definite conclusion. (biomedcentral.com)
  • We paid special attention to the role of gene flow through the Sahara in the genetic differentiation between Northern Africans and Southern Europeans. (biomedcentral.com)
  • A surprising finding was that the observed gene flow was substantial on most autosomal chromosomes but negligible on the Z chromosome, one of the sex chromosomes," said Fan Han, a graduate student at Uppsala University, who analysed these data as part of her Ph.D. thesis. (princeton.edu)
  • Chromosomes from reconstructed field bean ( Vicia faba L.) karyotypes were flow-sorted and the DNA was used for the physical localization of seed storage and nonstorage (USP) protein genes using PCR with sequence specific primers. (springer.com)
  • Arumuganathan K, Slattery JP, Tanksley SD, Earle ED (1991) Preparation and flow cytometric analysis of metaphase chromosomes of tomato. (springer.com)
  • Cotter F, Nasipuri S, Lam G, Young BD (1989) Gene mapping by enzymatic amplification from flow-sorted chromosomes. (springer.com)
  • Lucretti S, Doležel J, Schubert I, Fuchs J (1993) Flow karyotyping and sorting of Vicia faba chromosomes. (springer.com)
  • 1993) Localization of vicilin genes via polymerase chain reaction in microisolated field bean chromosomes. (springer.com)
  • Seven of these loci were localized close to the centromeres of chromosomes 10 and 12, with the prediction that these regions on the race-specific chromosomes would be the most likely to experience a barrier to gene flow. (whiterose.ac.uk)
  • Therefore, the centromeric regions of race-specific chromosomes do appear to experience a barrier to gene flow, although this can break down under intense interbreeding between the races. (whiterose.ac.uk)
  • We also showcase an example application to an Antirrhinum majus (snapdragon) flower-color hybrid zone, where we do not detect any signal of a strong genome-wide barrier to gene flow. (genetics.org)
  • The speciation-with-gene-flow model posits that the genome is semi-permeable and hybridization may be a phase in the process of divergence. (nih.gov)
  • The team conducted whole genome, whole exome and gene expression analysis of tumors in three patients using DNA and RNA found inside exosomes circulating in their blood or other liquid biospecimens. (eurekalert.org)
  • Full RNA sequencing is important because genome sequencing tells you what genes are altered, while analysis of RNA tells you what abnormal genes are actually being expressed," he said. (eurekalert.org)
  • Whole genome sequencing covered up to 91 percent of the human genome while exome sequencing of only the protein-coding genes covered 95 to 99 percent. (eurekalert.org)
  • Short pulses of high electric fields are applied to make the cell membranes transiently porous so that the genes ormolecules can enter the cells and modify the genome of the cells. (patentgenius.com)
  • We seek a bright, independent, organized, motivated individual to work on exciting projects based on genome editing and therapeutic gene transfer. (themuse.com)
  • Our findings also reveal that hybrids with only one type of the X chromosome ( e.g. , males) have more genes expressed at inappropriate levels compared with hybrids that have 2 copies of the X chromosome section of the genome ( e.g. , females). (uiowa.edu)
  • For many halobacterial groups the consensus phylogenetic signal derived from intein sequences is compatible with vertical inheritance or with a strong gene transfer bias creating these clusters. (frontiersin.org)
  • We measured male movement directly during a two year mark-recapture study, and indirectly with gene flow estimates from mitochondrial DNA sequences (mtDNA). (scielo.sa.cr)
  • Using mtDNA ND1 gene sequences, we quantified gene flow within and among headwater streams at two spatial scales: among headwater streams within two adjacent watersheds (2.5 km 2 ) and among streams within a longitudinal gradient covering 5.0 km 2 . (scielo.sa.cr)
  • It has become clear that DNA sequences from a multitude of genes, as well as a broad sample coverage of a target population, are needed to obtain a relatively unbiased view of its genetic structure and the patterns of ancestry connected to the strains. (nih.gov)
  • The results expose that-similarly to computers-the material components that enable the expression flow are well separated physically and they decipher the sequences through a distinct tridimensional arrangement with no indication of transcription/translation coupling. (asm.org)
  • A sample of mitochondrial DNA sequences revealed that at least four female mice must have founded the Waikawa population, but that gene flow between island and mainland mice is limited. (newzealandecology.org)
  • NADH subunit 4 (ND4) mtDNA gene sequences were taken from the National Center for Biotechnology Information (NCBI) constituting 39 localities and a sample size of 65 individuals of 46 haplotypes . (ccsu.edu)
  • Gene sequences were bootstrapped with 95 replicates and 10 random additions with all characters being unwieghted to generate a phylogenetic tree . (ccsu.edu)
  • A computer program that generated a haplotype cladogram using the gene sequences were used to determine nesting levels . (ccsu.edu)
  • Here we investigated the nucleotide diversity, divergence and gene flow between Oryza nivara and O. rufipogon using sequences of seven chloroplast and nuclear loci. (semanticscholar.org)
  • The unique combination of long-term field observations and genomic data shows that the reduction of gene flow for Z-linked loci primarily reflects female-biased gene flow, arising from a hybrid-male disadvantage in competition for high-quality territories and mates, rather than from genetic incompatibilities at Z-linked loci. (nature.com)
  • We have examined whether gene flow is responsible for the limited population structure in the Atlantic cod, Gadus morhua L., by comparing the previously published patterns of variation at 10 allozyme loci to 17 nuclear restriction fragment length polymorphism (RFLP) loci scored by 11 anonymous cDNA clones. (deepdyve.com)
  • Taking advantage of eight years (2006-2013) of genetic survey data (18 microsatellite loci) from a snow vole (Chionomys nivalis) population in the Swiss Alps, we explore whether and how gene flow and selection shape temporal variability in genetic diversity by counteracting the effect of genetic drift, and thereby maintain the high levels of heterozygosity observed in this population. (uzh.ch)
  • Each 11-loci barcode provides evidence supporting allele distribution gradient related to subpopulations and gene flow. (biomedcentral.com)
  • The 11-loci barcode successfully identifies recently emerging parasite subpopulations in western Cambodia that are associated with the C580Y dominant allele for artemisinin resistance in k13 gene. (biomedcentral.com)
  • It is not yet clear whether this discrepancy is due to incomplete lineage sorting or massive male-mediated gene flow. (uni-potsdam.de)
  • The genes are located within defined regions of chromosome I (USP= u nknown seed p rotein genes), II (vicilin genes, legumin B3 genes), III (legumin B4 genes), IV (pseudogenes ψ1) and V (legumin A genes and pseudogenes ψ1). (springer.com)
  • Except for the pseudogene derived from the sequence of legumin B4 gene, all members of each gene family are located in one chromosome region exclusively. (springer.com)
  • Collard JG, de Boer PAJ, Janssen JWG, Schijven JF, de Jong B (1985) Gene mapping by chromosome spot hybridization. (springer.com)
  • 2004). Phylogeography of Y-chromosome haplogroup I reveals distinct domains of prehistoric gene flow in Europe. (etis.ee)
  • Gene flow mediates the role of sex chromosome meiotic drive during com" by Colin D. Meiklejohn, Emily L. Landeen et al. (unl.edu)
  • Our findings reveal a high density of genetic incompatibilities and a corresponding dearth of gene flow on the X chromosome. (unl.edu)
  • In the second research aim of my dissertation, I assess the rates of gene expression evolution for sex-biased genes located on the X chromosome and autosomes. (uiowa.edu)
  • Calcitonin gene-related peptide (CGRP) and substance P (SP) which is potent vasodilator neuropeptides play a counter-regulatory role in several models of experimental hypertension. (academicjournals.org)
  • Objective The purpose of this study was to determine how calcitonin gene related peptide (CGRP) via axon reflex participates in increasing local muscle blood flow (MBF) following manual acupuncture (MA). (bmj.com)
  • 1991) Legumin of Vicia faba major: Accumulation in developing cotyledons, purification, mRNA characterization and chromosomal location of coding genes. (springer.com)
  • This arrangement was maintained even when the xyl genes were artificially relocated to different chromosomal locations. (asm.org)
  • Hence, considerable chromosomal differences between the groups do not prevent female gene flow, while male gene flow is reduced (cf. (diva-portal.org)
  • Methods We sequenced the mitochondrial ATPase-6 and ATPase-8 genes and the control region of 130 individuals collected throughout the range of the spe- cies in Mexico. (nlbif.nl)
  • The two A. cyanocephala mitochondrial DNA (mtDNA) groups corresponding with morphological and environmental niche differences, in concert with the results of a coalescent-based test, suggest that selection has been strong enough to counteract the effects of gene flow. (nlbif.nl)
  • We determined that introgressive hybridization is the cause of mtDNA/morphology incongruence because there are non-zero levels of migration and gene flow. (nih.gov)
  • In population genetics, gene flow (also known as gene migration) is the transfer of genetic variation from one population to another. (wikipedia.org)
  • The new study , published in Molecular Biology and Evolution , began when Aritra Bose, who earned his doctorate at Purdue in genetics and data science, was researching the close ties between genes and geography in Europe. (bigthink.com)
  • The Wisconsin scientists discovered the gene in Arabidopsis thaliana, a small plant used worldwide to study plant genetics, physiology and molecular biology. (bio-medicine.org)
  • Following a brief introduction that highlights general considerations when analyzing plant cells by flow cytometric methods, the book goes on to discuss examples of application in plant genetics, genomic analysis, cell cycle analysis, marine organism analysis and breeding studies. (wiley.com)
  • Efforts to find disease genes using high-density single-nucleotide polymorphism (SNP) maps will produce data sets that exceed the limitations of current computational tools. (nih.gov)
  • Results- In the angiotensinogen gene, only the rs699 single nucleotide polymorphism was associated with vasoreactivity after Bonferroni correction ( P =0.00028). (ahajournals.org)
  • We show that sparse binary trees represent patterns of gene flow in general pedigrees in a parsimonious manner, and derive a family of related algorithms for pedigree traversal. (nih.gov)
  • Recent divergence with gene flow in Tennessee cave salamanders (Plethodontidae: Gyrinophilus) inferred from gene genealogies. (amphibiatree.org)
  • These results strongly favour the hypothesis that Tennessee cave salamanders originated from spring salamanders via divergence with gene flow. (amphibiatree.org)
  • These findings highlight the contrasting population genetic dynamics that can occur at separate frontiers of a single population, while also suggesting that shared patterns may frequently accompany cases of divergence-with-gene-flow that involve a lineage in common. (gc.ca)
  • 5. The method of claim 1 , further comprising a second flow-through mixer, wherein the second flow-through mixture allows for the introduction of a third and/or fourth molecular entity-containing solution into the uniform mixture. (google.es)
  • Working with plant molecular biologist Richard Amasino in the Department of Biochemistry, Doyle identified the new gene, which they called early flowering 4 (ELF4). (bio-medicine.org)
  • Molecular genetic results from the study population Rautialp show that both pollen and seed dispersal occur across the entire stand, supporting the assumption of extensive gene flow through far-ranging vectors like wind and birds. (uzh.ch)
  • Results: We assessed variation at 96 SNPs and the Eda gene that affects lateral plate number, conducted molecular sex identification, and analyzed morphological traits. (dtu.dk)
  • The emergence of artemisinin resistance has been observed in this area since 2008-2009 and molecular signatures associated to artemisinin resistance have been characterized in k13 gene. (biomedcentral.com)
  • For this reason,gene flow has been thought to constrain speciation by combining the gene pools of the groups, and thus, preventing the development of differences in genetic variation that would have led to full speciation. (wikipedia.org)
  • These results are considered in the context of Harrison's (1990) concept of the semipermeability of hybrid zones to gene exchange and in relation to parapatric speciation. (whiterose.ac.uk)
  • Gene flow can therefore mediate the effects of selfish genetic elements during speciation. (unl.edu)
  • Explain gene flow's significance in terms of its role in a) determining if speciation has occurred and b) in determining the rate at which speciation will occur. (wyzant.com)
  • the entire question is: In speciation, gene flow is a key concept that must always be considered. (wyzant.com)
  • Ecological divergence plays a prominent role in the process of speciation, but how divergence occurs in the face of gene flow is still less clear, and remains controversial among evolutionists. (semanticscholar.org)
  • 3) A geographic barrier to dispersal causes a drastic change in the gene frequencies at the barrier only when almost all of the individuals trying to cross the barrier are stopped. (genetics.org)
  • A barrier to gene flow distorts this classical pattern of isolation by distance. (genetics.org)
  • Here, we introduce an inference scheme that uses this signal to detect and estimate the strength of a linear barrier to gene flow in two dimensions. (genetics.org)
  • Main conclusions Our findings implicate the Isthmus of Tehuantepec as a permeable barrier driving recent diversification of A. cyanocephala in the pres- ence of gene flow. (nlbif.nl)
  • However our data suggest that the Mediterranean Sea was at least partially a barrier to gene flow between the two shores. (biomedcentral.com)
  • Fig. 4: Genomic regions resistant to gene flow. (nature.com)
  • Exosomes may actually paint a more complete picture of a tumor's genomic diversity because all genetic mutations present in primary and metastatic tumors would flow into a liquid biopsy via the exosomes, the researchers noted. (eurekalert.org)
  • To accomplish our goals, we used polymorphisms in and around the genomic regions of the F7 and F12 genes. (biomedcentral.com)
  • In this study, we evaluated the effects of adenovirus-mediated human tissue kallikrein gene (Ad.CMV-cHK) delivery in a mouse model of arterial remodeling induced by permanent alteration in shear stress conditions. (ahajournals.org)
  • Expression of human tissue kallikrein (HK) mRNA was detected in mouse carotid artery, aorta, kidney, heart, and liver, and recombinant HK was present in the urine and plasma of mice receiving HK gene. (ahajournals.org)
  • 12 13 14 15 Recently, adenovirus-mediated human tissue kallikrein (HK) gene delivery proved to be an efficient strategy to increase local or circulating kinin levels for a limited period of time. (ahajournals.org)
  • Since plants function the same way whether they are the result of natural selection, human selection, or gene modified, findings from cultivated plants or wild relatives will aid in assessing the environmental effects of all future introductions of GM crops. (lu.se)
  • Since the biosafety certificates were issued to Bt transgenic rice containing cry1Ac gene against lepidopteran pests, concerns are raised on the gene flow from transgenic rice to its wild relatives. (semanticscholar.org)
  • The gradient of North African ancestry accounts for previous observations of low levels of sharing with Sub-Saharan Africa and is independent of recent gene flow from the Near East. (pnas.org)
  • The results are: (1) there is a characteristic length scale of variation of gene frequencies, (see PDF). (genetics.org)
  • University of Florida researchers have identified a gene variation in heart disease patients who appear especially vulnerable to the physical effects of mental stress - to the point where blood flow to the heart is greatly reduced. (innovations-report.com)
  • Those with the gene variation are three times more likely to experience dangerous decreases in blood flow to the heart - a condition doctors call ischemia - than heart disease patients without it. (innovations-report.com)
  • About a fourth of the patients experienced mental stress-induced reduced blood flow to the heart, and about two-thirds of them harbored a particular variation of the adrenergic beta-1 receptor genotype that was associated with a three-fold increased risk of this phenomenon, said Mustafa Hassan, M.D., the study's lead author and a research fellow in UF's division of cardiovascular medicine. (innovations-report.com)
  • This scenario is discussed within the background of current knowledge on the three-dimensional organization of the gene expression flow in other bacteria and the environmental lifestyle of this soil microorganism. (asm.org)
  • This approach proved to be useful for localizing genes that cannot be mapped genetically (due to the lack of allelic variants) and might be applied to integrate physical and genetic maps. (springer.com)
  • If you are an organic farmer, you may be worried your crops can be "contaminated" by a field genetically modified with a gene to express a natural toxin against pests. (science20.com)
  • These results indicate that in addition to natural dispersal, human-mediated gene flow also contributes to the generation and dynamics of the metapopulation genetic structure of A. alternata in China. (frontiersin.org)
  • The remaining 17.1% of genes comes from various sources while none of them contributes a proportion larger than 3% and therefore are not displayed due to the pruning. (nih.gov)
  • For example, eye color is coded by different alleles of the same gene. (khanacademy.org)
  • Estimates of gene flow from the private alleles method were similar for the allozymes and nuclear RFLPs. (deepdyve.com)
  • Our analysis combines group-centric and gene-centric perspectives, allows for arbitrary strength of selection, and leads to extensions of Hamilton's rule for the spread of altruistic alleles, applicable under broad conditions. (escholarship.org)
  • Physical barriers to gene flow are usually, but not always, natural. (wikipedia.org)
  • Barriers to gene flow need not always be physical. (wikipedia.org)
  • Can secondary contact following range expansion be distinguished from barriers to gene flow? (peerj.com)
  • CONCLUSIONS: We conclude that a zebrafish model of flow manipulation coupled to gene knockdown can be used for functional screening of mechanosensitive genes in vascular ECs, thus providing potential therapeutic targets to prevent or treat endothelial injury at atheroprone sites. (whiterose.ac.uk)
  • Conclusions: We suggest that gene flow from marine sticklebacks overwhelms adaptation to freshwater conditions, but the short genetic patch size means that the effect of gene flow on the most upstream region must be indirect and occurs over generations. (dtu.dk)
  • We then used the presence-absence profile, sequence similarity and phylogenies from the inteins recovered to explore how intein distribution can provide insight on the dynamics of gene flow between closely related and divergent organisms. (frontiersin.org)
  • Contrary to mtDNA patterns, we found (i) brown and polar bears to be reciprocally monophyletic sister (or rather brother) lineages, without signals of introgression, (ii) male-biased gene flow across continents and on phylogeographic time scales, and (iii) male dispersal that links the Alaskan ABC-islands population to mainland brown bears. (datadryad.org)
  • Bayesian coalescent theory was used to estimate contemporary and historical gene flow. (biomedcentral.com)
  • High levels of contemporary gene flow were detected from the YBS (north) to the ECS (south), whereas low levels of historical gene flow occurred between the two regions. (biomedcentral.com)
  • Background and Purpose- Our objective was to investigate the associations between polymorphisms in representative genes of the renin angiotensin system with measures of cerebral blood flow regulation in older adults. (ahajournals.org)
  • A total of 33 tagged single nucleotide polymorphisms were selected in the angiotensinogen gene, the angiotensin converting enzyme gene, and the angiotensin receptor gene. (ahajournals.org)
  • None of the single nucleotide polymorphisms in the other genes were associated with our phenotypes. (ahajournals.org)
  • Further, renin angiotensin system gene polymorphisms are associated with angiotensin II levels and measures of systemic blood pressure regulation 10 and baroreflex sensitivity. (ahajournals.org)
  • 11 Therefore, we hypothesized that polymorphisms in genes of the renin angiotensin system are also associated with autoregulation and the cerebrovascular response to changes in CO 2 . (ahajournals.org)
  • In the various embodiments, the present invention provides controlled and uniform mixing of gene therapy vectors and gene therapy vector vehicles for improved reproducibility, scaleability, stability, and pharmaceutical efficacy. (google.es)
  • Mutation, migration (gene flow), genetic drift, and natural selection are the four mechanisms that lead to biological evolution, or a change in allele frequencies in a population over time. (science20.com)
  • We find that gene expression evolves faster in males than females and find evidence of faster-X evolution that is exclusive to genes expressed at higher levels in males. (uiowa.edu)
  • Gene flow is a major evolutionary force and an important factor in the breeding and conservation of forest trees. (oregonstate.edu)
  • Assemblage B had the highest level of both haplotype diversity and nucleotide diversity, followed by assemblage E. The analysis also revealed population expansion and high gene flow in all assemblages. (biomedcentral.com)
  • Our primary interest is in understanding what this new gene does to control flowering, but it may be difficult to separate that from its effects on the clock that determines plant rhythms," says Doyle, a research assistant in the College of Agricultural and Life Sciences. (bio-medicine.org)
  • So far, scientists haven't found any genes similar to ELF4 outside the plant kingdom," Amasino says. (bio-medicine.org)
  • When I first started doing plant paternity studies in the 1980s," Ellstrand comments, "our lab assumed that gene flow was limited. (science20.com)
  • The population is so strongly isolated that gene flow is not a possibility leading to high occurrences of inbreeding. (wikipedia.org)
  • Our study challenges the idea that high gene flow precludes local adaptation, and provides unique experimental evidence of habitat choice as an overlooked mechanism responsible for adaptation under rapid environmental changes. (nature.com)
  • Requiring multiple mismatches for paternity exclusion, while assuring that the probability of detecting immigrant genotypes is high, results in accurate estimates of pollen flow. (oregonstate.edu)
  • We found that the tiger metapopulation in central India has high rates of historical and contemporary gene flow. (royalsocietypublishing.org)
  • While catabolic traits of this sort are not uncommon in many other environmental isolates, what makes the TOL system special is the extraordinary regulatory intricacy that controls expression of the xyl genes and their high-level interplay with the host's physiological regulons. (asm.org)
  • This pattern may be a consequence of the Neolithic demic diffusion in this region (around 10,000 years before present) and/or a high level of gene flow in the area. (biomedcentral.com)
  • Altruism can proliferate through population viscosity despite high random gene flow. (escholarship.org)
  • And plants are very well suited for studies on gene flow because individuals are stationary yet pollen and seeds are mobile. (science20.com)
  • This thesis illustrates the effects of environmental factors on pollen performance and its importance on gene flow. (lu.se)
  • Because pollen performance influences gene flow, an understanding of the factors affecting pollen performance is fundamental when conducting risk assessment studies. (lu.se)
  • I studied the applicability of SSR markers for measuring pollen-mediated gene flow (i.e., pollen flow) in Douglas-fir (Pseudotsuga menziesii [Mirb. (oregonstate.edu)
  • I developed SSR markers, tested alternative approaches for measuring pollen flow using SSR markers, then measured pollen contamination and characterized within-block mating patterns in one block of a seed orchard complex. (oregonstate.edu)
  • Mistyping (i.e., false identification of genotypes) results in overestimating pollen flow. (oregonstate.edu)
  • I developed and made available the Pollen Flow (PFL) computer program, which performs paternity exclusion and measures pollen flow based on multiple fatheroffspring mismatches. (oregonstate.edu)
  • Pollen-mediated gene flow between glyphosate-resistant Brassica napuscanola and B . juncea and B . carinata mustard} crops under large-scale field conditions in Saskatchewan. (gc.ca)
  • Merlin--rapid analysis of dense genetic maps using sparse gene flow trees. (nih.gov)
  • Population structure analysis revealed existence of a gene flow between O. sativa and O. glaberrima rice accessions which can be used to combine several interesting traits in breeding programs. (springer.com)
  • Conclusion- This analysis suggests that the angiotensinogen gene may be involved in vasoreactivity independent of blood pressure. (ahajournals.org)
  • I remain skeptical about the mainstream story about what this involvement is (Neandertal-to-Eurasian gene flow), and this analysis certainly seems consistent with the alternative (AMH-to-Neandertal gene flow during the expansion of modern humans out of the Near East). (blogspot.com)
  • The admixture arrows are uniformly directed from N. meningitidis towards N. lactamica, implying that N. meningitidis might donate genetic materials into N. lactamica, while the gene flow in a reversed direction is not supported by the analysis. (nih.gov)
  • This introgression is much earlier than previously reported gene flow from Neanderthals into modern humans outside Africa (47,000-65,000 years ago). (eurekalert.org)
  • Occurrence and ecological consequences of transgenic rice gene flow: a review]. (semanticscholar.org)
  • To fully exploit the diversity in African rice germplasm and to broaden the gene pool reliable information on the population genetic diversity and phenotypic characteristics is a prerequisite. (springer.com)
  • Genes that displayed the greatest differential expression and possessed 1 to 2 zebrafish orthologues were screened for the regulation of apoptosis in zebrafish vasculature exposed to flow or no-flow conditions using a knockdown approach. (whiterose.ac.uk)
  • A model of the effect of gene flow and natural selection in a continuously distributed, infinite population is developed. (genetics.org)
  • Results The data revealed two genetic groups separated by the Isthmus of Tehuantepec in the late Pleistocene (49,300-75,800 years ago), with the split occurring in the presence of gene flow. (nlbif.nl)
  • Ellstrand says that evolutionary biologists' view on the importance of gene flow has waxed and waned over the last century. (science20.com)
  • The second hypothesis is that gene flow from the Near East, associated with the demic diffusion of agriculture, differentially affected geographic regions and in particular introduced additional genetic diversity to southeastern Europe ( 6 , 7 ). (pnas.org)
  • For tigers specifically, there is no published information available about landscape-level gene flow, meaning we do not know enough about how habitat connectivity may influence genetic diversity and population persistence in a metapopulation context. (royalsocietypublishing.org)
  • Further studies are needed to clarify the contributions of this gene flow to valuable traits such as abiotic and biotic stresses including disease resistance. (springer.com)
  • Because blood flow regulation and vascular reactivity are heritable traits (h 2 is ≥60%), a genetic association study is justifiable. (ahajournals.org)
  • From the infinite island model, however, estimates of gene flow from the DNA markers were fivefold lower than indicated by the proteins. (deepdyve.com)
  • Local adaptation is assumed to occur under limited gene flow. (nature.com)
  • The availability of large sets of highly variable SSRs makes it possible to perform landscape-scale studies of gene flow and better understand the interactions between gene flow and adaptation. (oregonstate.edu)