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HeterozygoteHeterozygote DetectionHomozygoteMutationAllelesCell SurvivalGenotypePedigreePhenotypeMicrobial ViabilityFetal ViabilityTissue SurvivalPolymorphism, GeneticGene FrequencyGenes, LethalThalassemiaMolecular Sequence DataBase SequenceGenes, RecessiveCrosses, GeneticHyperlipoproteinemia Type IHemoglobin A2Genes, DominantGenetic VariationDNA Mutational AnalysisPolymerase Chain ReactionPoint MutationApoptosisHemoglobins, AbnormalCells, CulturedHemochromatosisGenetic Predisposition to DiseaseAtaxia TelangiectasiaMutation, MissenseHaplotypesHyperlipoproteinemia Type IIModels, GeneticExonsCystinuriaHypobetalipoproteinemiasTay-Sachs DiseaseHemoglobin EGenetic LinkageMice, Mutant StrainsJewsAdenine PhosphoribosyltransferaseInbreedingDNAMice, KnockoutGene DeletionChromosome MappingAmino Acid SequenceFetal HemoglobinGenetic TestingTime Factorsalpha-ThalassemiaGenetics, PopulationPolymorphism, Single NucleotideMice, Inbred C57BLSelection, GeneticFibroblastsHemoglobinopathiesGenetic MarkersCell LinePolymorphism, Restriction Fragment LengthShrewsDNA PrimersSandhoff DiseaseDrosophila melanogasterCell Line, TumorMicrosatellite RepeatsRNA, Messengerbeta-ThalassemiaGlucosephosphate Dehydrogenase DeficiencyAmino Acid Metabolism, Inborn ErrorsCell ProliferationPhenylketonuriasFrameshift MutationCryopreservationHybrid VigorGlobinsCase-Control StudiesCodon, NonsenseMembrane ProteinsSequence Analysis, DNARecombination, GeneticLipid Metabolism, Inborn ErrorsMetabolism, Inborn ErrorsSequence DeletionHaploidyGenetic Complementation TestCrossing Over, GeneticFabry DiseaseHypolipoproteinemiasTetrazolium SaltsDiploidyGenesConsanguinityDose-Response Relationship, DrugHexosaminidase A
HomozygotesExhibiting heterozygote advantageHomozygoteAllelePhenotypeFrequency-dependentFertilityGeneMutationAdvantageEstimatesEquivalentFitnessMaintained by selectionGeneticWild typeEffectsMajorLossActivityCell viabilityHeterozygousRecessiveLethalitySurvivalPrimarilyDominantMiceViableClinicalHumansRequired for normalPopulationCaseFunction
Homozygotes6
  • A common example is the case where the heterozygote conveys both advantages and disadvantages, while both homozygotes convey a disadvantage. (wikipedia.org)
  • The heterozygote expressed none of the disadvantages of homozygotes, yet gained improved viability. (wikipedia.org)
  • The chromosomal translocation generates a translocation-bearing altered insect population, the translocation-bearing altered insect population comprises translocation-bearing individuals that are translocation heterozygotes and translocation-bearing individuals that are translocation homozygotes for the chromosomal translocation, and the translocation-bearing individuals display a fitness that is greater than that of the wildtype (non-translocation-bearing) individuals when challenged in a condition in which a translocation-based drive occurs. (justia.com)
  • Allele polymorphisms at loci in the MHC and locus are thought to be managed by balancing selection, either by overdominance (heterozygotes have a higher fitness than homozygotes) or by frequency dependent selection (rare alleles are at a selective advantage, but become disadvantageous when common) (4, 6, 7). (liveconscience.com)
  • In the event the gametes are set while in the lattice from the arrangement, that will be exhibited from the structure, the grille you may start to see the sequence from the arrangement of genotypes: one particular grille are homozygotes, whereas heterozygotes for just two enzymes. (smokeoilsalt.com)
  • Inbreeding results in an excess of homozygotes and hence a deficiency of heterozygotes. (lacteoscienelac.com)
Exhibiting heterozygote advantage1
Homozygote5
Allele3
  • Heterozygote advantage for the phenylketonuria allele. (bmj.com)
  • This near-optimal birthweight together with the possibly higher effective fertility observed in PKU heterozygous couples (at least in those who married before 1940), has apparently more than outweighed the disadvantages of the allele in PKU homozygous offspring as shown, for example, in an excessive number of pre- and perinatal deaths among the total offspring of PKU heterozygotes, to say nothing of the PKU survivors who, often, used to die young. (bmj.com)
  • This heterozygote advantage presumably explains the presence of the allele at frequencies above those to be expected from the simple replacement of a homozygously-lethal allele by mutation alone. (bmj.com)
Phenotype1
  • Evolution then approaches a population state where every phenotype has maximum viability in one of the two patches. (iiasa.ac.at)
Frequency-dependent1
  • Pathogen-mediated selection results in positive selection and the substitution of amino acids in the codons of the peptide-binding region (PBR), as well as balancing selection including heterozygote advantage, frequency-dependent selection and fluctuating selection [ 2 , 4 , 14 ]. (biomedcentral.com)
Fertility3
  • The two effects--fertility and viability--apparently both contribute in the same direction, to give a biological fitness in excess of 1 for the heterozygote. (bmj.com)
  • Therefore we studied the relation between heterozygote frequency and fertility rates, disregarding the characterization for incidence of malaria. (indexarticles.com)
  • The aims of this study are to test the hypothesis that differential fertility is a selection-induced mechanism that maintains balanced polymorphisms and to investigate the reasons for and the effects on reproduction of the incomplete correspondence of heterozygote frequency and malarial morbidity levels on Sardinia. (indexarticles.com)
Gene5
  • A well-established case of heterozygote advantage is that of the gene involved in sickle cell anaemia. (wikipedia.org)
  • This mutation, which at first glance appeared to be harmful, conferred enough of an advantage to heterozygotes to make it beneficial, so that it remained at dynamic equilibrium in the gene pool. (wikipedia.org)
  • Haldane's (1949) theory of a selective advantage of heterozygotes in the presence of malaria has been largely tested and confirmed, principally for the sickle cell gene and glucose-6-phosphate dehydrogenase (G6PD) deficiency, in areas where malaria is still endemic (Africa, tropical zones). (indexarticles.com)
  • These studies would not determine a new heterozygote gain pertaining to CF gene strains regarding cancer threat. (hspsignaling.com)
  • Heterozygote AG variant of -596 A/G IL-6 gene polymorphism is a marker for cutaneous T-cell lymphoma (CTCL). (cdc.gov)
Mutation3
  • In a classic study on the ebony mutation, Kalmus demonstrated how polymorphism can persist in a population through heterozygote advantage. (wikipedia.org)
  • However, the same mutation also conveyed advantages, providing improved viability for heterozygous individuals. (wikipedia.org)
  • We sequenced the coding regions surrounding YXXM motifs of IRS1 using tumor samples of 42 NSCLC patients and 40 matching controls and found heterozygote p.S668T mutation in nine of 42 samples and four of nine also had the p.D674H mutation. (scielo.br)
Advantage7
  • A heterozygote advantage describes the case in which the heterozygous genotype has a higher relative fitness than either the homozygous dominant or homozygous recessive genotype. (wikipedia.org)
  • The specific case of heterozygote advantage due to a single locus is known as overdominance. (wikipedia.org)
  • Heterozygote advantage is a major underlying mechanism for heterosis, or "hybrid vigor", which is the improved or increased function of any biological quality in a hybrid offspring. (wikipedia.org)
  • Previous research, comparing measures of dominance, overdominance and epistasis (mostly in plants), found that the majority of cases of heterozygote advantage were due to complementation (or dominance), the masking of deleterious recessive alleles by wild-type alleles, as discussed in the articles Heterosis and Complementation (genetics), but there were also findings of overdominance, especially in rice. (wikipedia.org)
  • More recent research, however, has established that there is also an epigenetic contribution to heterozygote advantage, primarily as determined in plants, though also reported in mice. (wikipedia.org)
  • The first experimental confirmation of heterozygote advantage was with Drosophila melanogaster, a fruit fly that has been a model organism for genetic research. (wikipedia.org)
  • We test for a heterozygote advantage on other fitness components but find no evidence for heterosis for any of the inversions. (biomedcentral.com)
Estimates1
  • A sample of Sardinian villages is classified according to the estimates of heterozygote frequency obtained by Siniscalco et al. (indexarticles.com)
Equivalent1
Fitness1
  • However, the first demonstration of the higher fitness (in terms of number of children) of heterozygotes comes from a study on thalassemia in Italy, when Haldane's hypothesis had only just been formulated. (indexarticles.com)
Maintained by selection1
  • Polymorphism can be maintained by selection favoring the heterozygote, and this mechanism is used to explain the occurrence of some kinds of genetic variability. (wikipedia.org)
Genetic2
  • However, Zei's analysis did not comprehensively confirm Haldane's theory, because in each homogeneous area of malaria incidence the villages for which genetic data were also available showed high heterogeneity with respect to heterozygote frequencies for thalassemia and G6PD deficiency. (indexarticles.com)
  • The viability of such heterokaryons is determined by the genetic constitution at ((loci can give rise to unstable nuclear ratios or can result in growth inhibition of heterokaryotic cells, which are frequently damaged by a lytic process (8, 9, 12, 13). (liveconscience.com)
Wild type1
  • While complete loss of catalase activity confers a severe viability effect, residual levels are sufficient to restore viability to wild type levels. (lookformedical.com)
Effects1
  • These results suggest a threshold effect for viability and offer an explanation for the general lack of phenotypic effects associated with the known mammalian acatalasemics. (lookformedical.com)
Major1
  • Heterozygotes for major chromosomal rearrangements such as fusions and fissions are expected to display a high level of sterility due to problems during meiosis. (frontiersin.org)
Loss1
  • Inhibitors,research,lifescience,medical This function is required for health and viability with age, especially within the nervous system, and loss of this function is known to be deleterious. (phosphorylase-signal.com)
Activity1
  • The expanded line was evaluated for viability surface antigen expression and alkaline phosphatase activity. (coriell.org)
Cell viability2
  • This deadenylation deficiency caused an early DNA damage response in terms of nuclear p53 regulation, cell-cycle arrest, and reduced cell viability upon UV treatment. (jci.org)
  • Additionally, hCMEC/D3 cell viability was not affected by Aβ peptides or by Aβ-MAb-LIP. (stabvida.com)
Heterozygous3
  • A heterozygote advantage describes the case in which the heterozygous genotype has a higher relative fitness than either the homozygous dominant or homozygous recessive genotype. (wikipedia.org)
  • Overdominance is a rare condition in genetics where the phenotype of the heterozygote lies outside of the phenotypical range of both homozygote parents, and heterozygous individuals have a higher fitness than homozygous individuals. (wikipedia.org)
  • However, the same mutation also conveyed advantages, providing improved viability for heterozygous individuals. (wikipedia.org)
Recessive3
  • Previous research, comparing measures of dominance, overdominance and epistasis (mostly in plants), found that the majority of cases of heterozygote advantage were due to complementation (or dominance), the masking of deleterious recessive alleles by wild-type alleles, as discussed in the articles Heterosis and Complementation (genetics), but there were also findings of overdominance, especially in rice. (wikipedia.org)
  • Adenosine Deaminase (ADA) deficiency is an autosomal recessive disorder of purine metabolism primarily affecting lymphocyte development, viability, and function. (clevelandcliniclabs.com)
  • The nonviable XX, YY and ZZ possibilities would mean 1 in 4 conceptions would end in miscarriage as is the case with humans when the 2 parents are heterozygotes for a recessive gene which is lethal as the homozygote. (stackexchange.com)
Lethality1
  • A) An enhancer-suppressor screen of 3663 individual P-element insertion lines identified 40 candidate insertions that LG 100268 enhance or suppress the toxicity of dominant … Insertion lines were categorized as either enhancers or suppressors based on the effects around the lethality compared with heterozygote controls. (morainetownshipdems.org)
Survival2
  • The homozygote wild type was perfectly healthy, but did not possess the improved viability of the heterozygote, and was thus at a disadvantage compared to the heterozygote in survival and reproduction. (wikipedia.org)
  • However, while a diverse range of fitness costs are reported in the field, they are typically represented as a fixed reduction in survival or viability which is insensitive to ecological conditions such as competition. (ox.ac.uk)
Primarily1
  • More recent research, however, has established that there is also an epigenetic contribution to heterozygote advantage, primarily as determined in plants, though also reported in mice. (wikipedia.org)
Dominant2
  • Reasons why Ds not seen in other v@sitions: Produce either lethal condition in heterozygote -- dominant lethal, or very much reduced viability, a). (nih.gov)
  • Kezrmels from abcut half of the cascs of transvesition of Ds to new positions did not give plants even when they apnesred to be normal, ec), Study of effets of Ds when located between I and Sh -- produces dominant lethals or low viabilities in heterozygote -= will be discussed latcr, 4. (nih.gov)
Mice1
  • These experiments reveal that lincRNAs have a strong influence on the overall viability of mice, and also on a number of developmental processes, including the development of lungs and the cerebral cortex. (elifesciences.org)
Viable1
  • Meiotic drivers are selfish elements that bias their own transmission into more than half of the viable progeny produced by a driver+/driver- heterozygote. (geneconvenevi.org)
Clinical1
  • 8. Mild orotic aciduria in UMPS heterozygotes: a metabolic finding without clinical consequences. (nih.gov)
Humans1
Required for normal2
  • To enrich for the recovery of insertions required for normal motor neuron function we performed initial viability screens in backgrounds in which the function of the dynactin complex is usually impaired in motor neurons. (morainetownshipdems.org)
  • The protein functions to maintain the mitochondrial tubular shapes and is required for normal mitochondrial morphology and cellular viability. (utsouthwestern.edu)
Population1
Case1
Function1
  • Heterozygote advantage is a major underlying mechanism for heterosis, or "hybrid vigor", which is the improved or increased function of any biological quality in a hybrid offspring. (wikipedia.org)