• populations
  • The term " wild type " allele is sometimes used to describe an allele that is thought to contribute to the typical phenotypic character as seen in "wild" populations of organisms, such as fruit flies ( Drosophila melanogaster ). (wikipedia.org)
  • Because of pseudodeficiency alleles, the results of enzyme assay testing in one population cannot be generalized to other populations. (wikipedia.org)
  • These alleles are not commonly found in populations because they usually result in the death of an organism before it can transmit its lethal allele on to its offspring. (wikipedia.org)
  • Genetic drift causes changes in allele frequency from random sampling due to offspring number variance in a finite population size, with small populations experiencing larger per generation fluctuations in frequency than large populations. (wikipedia.org)
  • The JAFS for d {\displaystyle d} populations, with n j {\displaystyle n_{j}} sampled chromosomes in the j {\displaystyle j} th population, is a d {\displaystyle d} -dimensional histogram, in which each entry stores the total number of segregating sites in which the derived allele is observed with the corresponding frequency in each population. (wikipedia.org)
  • homologous
  • For example in human population genetic studies, the homologous chimpanzee reference sequence is typically used to estimate the ancestral allele. (wikipedia.org)
  • There are different DNA mutations of either type A or Type B alleles that change several amino acids in enzyme transferase A or B, homologous enzymes differing in only four of 354 amino acids (R176G, G235S, L266M, and G268A). (wikipedia.org)
  • genotype
  • However, this result only holds for the neutral case, and is not necessarily true for the case when some alleles are subject to selection, i.e. more or less fit than others, for example when the fittest genotype is a heterozygote (a situation often referred to as overdominance or heterosis). (wikipedia.org)
  • produces
  • A mutant allele that produces no protein is called a protein null (shown by western analysis), and one that produces no RNA is called an RNA null (shown by Northern analysis or by DNA sequencing of a deletion allele). (wikipedia.org)
  • The wild-type allele produces a blend of yellow and black pigmentation in each hair of the mouse. (wikipedia.org)
  • The A allele produces α-1,3-N-acetylgalactosamine transferase (A-transferase), which catalyzes the transfer of GalNAc residues from the UDP-GalNAc donor nucleotide to the Gal residues of the acceptor H antigen, converting the H antigen into A antigen in A and AB individuals. (wikipedia.org)
  • selective
  • Since East Asians and Europeans have already been subject to sweeps which moved them (presumably) to their phenotypic optimum the selective value of the introduced alleles is probably not that high. (gnxp.com)
  • The reason I'm focusing on alleles with selective value is that moments like the settlement of the Americas by a small group of Iberian men and the generation of a mestizo population within a century through hybridization are rare events. (gnxp.com)
  • neutral
  • These results became important in the formation of the neutral theory, because neutral (or nearly neutral) alleles create no such segregational load, and allow for the accumulation of a great deal of polymorphism. (wikipedia.org)
  • When Richard Lewontin and J. Hubby published their groundbreaking results in 1966 which showed high levels of genetic variation in Drosophila via protein electrophoresis, the theoretical results from the infinite alleles model were used by Kimura and others to support the idea that this variation would have to be neutral (or result in excess segregational load). (wikipedia.org)
  • 1,They showed that the age of a neutral allele can be estimated (assuming a large, randomly mating population) by E(t_1 )=(-2p)/(1-p) ln⁡(p) Where p represents the allele frequency and t1 is the expected age, measured in units of 2N generations. (wikipedia.org)
  • allelic
  • Estimating allele age based on intra-allelic variation is based on the fact that with every generation, linkage with other alleles (linkage disequilibrium) is disrupted by recombination and new variation in linkage is created via new mutations. (wikipedia.org)
  • The analysis of intra-allelic variation to assess allele age depends on coalescent theory. (wikipedia.org)
  • There are two different approaches that can be used to analyze allele age based on intra-allelic variation. (wikipedia.org)
  • In 1990, Jean-Louis Serre and his team were the first to assess allele age by analyzing intra-allelic variation. (wikipedia.org)
  • 3,Many intra-allelic variation studies suggest that disease-causing alleles arose rather recently in human history. (wikipedia.org)
  • mutations
  • The infinite alleles model is a mathematical model for calculating genetic mutations. (wikipedia.org)
  • Divergence from the reference sequences (from genetic mutations) results in poor annealing of the primers so that the marker cannot be used, representative of a null allele. (wikipedia.org)
  • population
  • Function: Sets and returns the frequency of the allele in the observed population. (cpan.org)
  • Enzyme assay testing was especially effective among Ashkenazi Jews because fewer pseudodeficiency alleles are found in this population, as compared with the general population. (wikipedia.org)
  • The effective number of alleles n maintained in a population is defined as the inverse of the homozygosity, that is n = 1 F = 4 N e u + 1 {\displaystyle n={1 \over F}=4N_{e}u+1} which is a lower bound for the actual number of alleles in the population. (wikipedia.org)
  • If the effective population is large, then a large number of alleles can be maintained. (wikipedia.org)
  • The demographic history of a population and natural selection affect allele frequency dynamics, and these effects are reflected in the shape of the allele frequency spectrum. (wikipedia.org)
  • carries
  • To improve on current reporter labeling strategies that employ, at most, two recombinases (Cre and Flp, typically), Dr. Jensen's team created a new strain that carries a reporter allele that will label cells defined by the overlapping expression of up to three different recombinases, (B6.Cg- Gt(ROSA)26Sor tm1.1(CAG-tdTomato,-EGFP)Pjen /J - stock number 026930 ). (jax.org)
  • carriers
  • If two cystic fibrosis carriers have children, they have a 25 percent chance of producing offspring having two copies of the lethal allele, eventually resulting in the death of the child. (wikipedia.org)
  • humans
  • The ABO system in humans is controlled by three alleles, usually referred to as I A , I B , and I O (the "I" stands for isohaemagglutinin). (encyclopedia.com)
  • So humans do not always have only two alleles for a given trait. (physicsforums.com)
  • An example in humans of a dominant lethal allele is Huntington's disease, a rare neurodegenerative disorder that ultimately results in death. (wikipedia.org)
  • different
  • For one trait there can be several sets of alleles, maybe all different, for a single trait. (physicsforums.com)
  • Hence an individual with "Type A" blood may be an AO heterozygote, an AA homozygote, or an AA heterozygote with two different "A" alleles. (wikipedia.org)
  • By observing the consequences of different inactive allele combinations, the researchers were able to deduce the roles of insulin-like growth factors in the development of mice. (wikipedia.org)
  • This method provided very different results, suggesting that the allele appeared more than 100,000 years ago. (wikipedia.org)
  • the slightly different variations of that sequence are called alleles. (wikipedia.org)
  • Alleles can be significantly different and produce different product RNAs. (wikipedia.org)
  • researchers
  • To demonstrate the utility of their new intersectional reporter allele, the researchers crossed the reporter-bearing mice with recombinase-expressing strains in order to label neural subpopulations in the noradrenergic system. (jax.org)
  • Estimating the time at which a certain allele appeared allows researchers to infer patterns of human migration, disease, and natural selection. (wikipedia.org)
  • incomplete
  • A pseudodeficiency allele may indicate a deficiency of the enzyme assay method, or it may reflect incomplete understanding of the enzyme's activity. (wikipedia.org)
  • Extended expression patterns seen in diploid organisms include facets of incomplete dominance, codominance, and multiple alleles. (wikipedia.org)
  • Incomplete dominance is the condition in which neither allele dominates the other in one heterozygote. (wikipedia.org)
  • enzyme activity
  • For example, in the lysosomal storage diseases, patients with a pseudodeficiency allele show greatly reduced enzyme activity, yet they remain clinically healthy. (wikipedia.org)
  • present
  • For some genetic diseases, especially those that have low penetrance or are easily treatable, carrier screening may be of questionable value when pseudodeficiency alleles are present at high frequency. (wikipedia.org)
  • Thus you can tell that each allele is present in the heterozygote. (wikipedia.org)
  • variant
  • Kompetitive Allele Specific PCR (KASP) is a homogenous, fluorescence-based genotyping variant of Polymerase Chain Reaction. (wikipedia.org)
  • novel
  • To overcome these challenges, a research team led by Dr. Patricia Jensen at the National Institute of Environmental Health Sciences in North Carolina developed a novel intersectional recombinase reporter allele that allows for labeling more refined and distinct subpopulations of cells. (jax.org)
  • describe
  • List of alleles describe known sequence alternatives in a variable region. (cpan.org)
  • In addition describing the allele by its sequence , it possible to give describe repeat structure within the sequence. (cpan.org)
  • sequence
  • Allele objects that have zero length sequence string. (cpan.org)
  • Function: Sets and returns the sequence of the repeat_unit the allele is composed of. (cpan.org)
  • An allele-specific oligonucleotide (ASO) is a short piece of synthetic DNA complementary to the sequence of a variable target DNA. (wikipedia.org)
  • The fluorescent labeled primer complements the tail sequence of the allele-specific forward primer, allowing for elongation to occur. (wikipedia.org)
  • common
  • There are three components that are critical to the KASP assay: 1) a purified DNA sample, 2) two allele-specific forward primers, and 3) a common reverse primer. (wikipedia.org)
  • In the second round of PCR, the complementary strand to the allele-specific forward primer is generated when the common reverse primer binds to the amplicon formed in the first round of PCR. (wikipedia.org)
  • There are six common alleles in individuals of European descent. (wikipedia.org)
  • Disease
  • A person exhibits Huntington's disease when they carry a single copy of a repeat-expanded Huntingtin allele on chromosome 4. (wikipedia.org)
  • Samples 2 and 6 have only the "S" allele, and would be affected by the disease. (wikipedia.org)