• polymorphisms
  • RESEARCH DESIGN AND METHODS In the Finnish Diabetic Nephropathy Study (FinnDiane) cohort, 37 tagging single nucleotide polymorphisms (SNPs) were genotyped in 2,991 individuals with type 1 diabetes and diabetic retinopathy, diabetic nephropathy, and cardiovascular disease. (diabetesjournals.org)
  • With the availability of genome-wide genotyping technologies, a large number of single nucleotide polymorphisms (SNPs) can be considered during epistasis detection (Heidema et al. (springeropen.com)
  • polymorphic
  • Eventually, a polymorphic "a" allele may be introduced into the population, resulting in an individual who is capable of exploiting a different resource. (wikipedia.org)
  • The most common situation arises when genotypes are collected at a set of polymorphic sites from a group of individuals. (wikipedia.org)
  • populations
  • In natural populations natural selection (adaptation mechanism), gene flow, and mutation combine to change allele frequencies across generations. (wikipedia.org)
  • In experimental populations, the ebony allele was more prevalent and therefore advantageous when flies were raised at low, dry temperatures, but less so in warm, moist environments. (wikipedia.org)
  • Both branches use the frequencies of different alleles of a gene in breeding populations (gamodemes), and combine them with concepts from simple Mendelian inheritance to analyze inheritance patterns across generations and descendant lines. (wikipedia.org)
  • The two groups of trees were treated as one population because no deviations from expected genotype frequencies were observed, as would be expected if the populations were diverging from one another. (wikipedia.org)
  • Compared to examples of overdominance in actual populations, underdominance is considered more unstable and may lead to the fixation of either allele. (wikipedia.org)
  • organisms
  • If in either monoecious or dioecious organisms, either the allele or genotype proportions are initially unequal in either sex, it can be shown that constant proportions are obtained after one generation of random mating. (wikipedia.org)
  • The seven assumptions underlying Hardy-Weinberg equilibrium are as follows: organisms are diploid only sexual reproduction occurs generations are nonoverlapping mating is random population size is infinitely large allele frequencies are equal in the sexes there is no migration, mutation or selection Violations of the Hardy-Weinberg assumptions can cause deviations from expectation. (wikipedia.org)
  • In diploid organisms, one allele is inherited from the male parent and one from the female parent. (wikipedia.org)
  • fixation
  • The dynamic system (1) has two monomorphic equilibria (1, 0, 0) and (0, 0, 1) corresponding to the fixation of genotype AA and aa , respectively. (genetics.org)
  • This system of underdominance allowed manipulation of the population and ultimate fixation of the constructed genotype and has potential applications in a number of settings, including agriculture and the reduction of various pest-carried diseases. (wikipedia.org)
  • allelic
  • The next major advance in genotyping technology was the advent of the TaqMan Allelic Discrimination assay. (immh.org)
  • More generally, where a gene exists in two allelic versions (designated A and a), three combinations of alleles are possible: AA, Aa, and aa. (wikipedia.org)
  • genetics
  • Seven SNPs were genotyped in the replication cohorts from the Steno Diabetes Center and All Ireland/Warren 3/Genetics of Kidneys in Diabetes (GoKinD) U.K. study. (diabetesjournals.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)
  • For example in human genetics, genome-wide association studies collect genotypes in thousands of individuals at between 200,000-5,000,000 SNPs using microarrays. (wikipedia.org)
  • genotypic
  • RESULTS In a meta-analysis, the minor T allele of the exonic SNP rs17353856 in the SUV39H2 was associated with diabetic retinopathy (genotypic odds ratio 0.75, P = 1.2 × 10 −4 ). (diabetesjournals.org)
  • The HWP states the population will have the given genotypic frequencies (called Hardy-Weinberg proportions) after a single generation of random mating within the population. (wikipedia.org)
  • trait
  • Individuals who are heterozygous for this trait appear to be intermediate in appearance and thus experience increased predation and lowered overall fitness. (wikipedia.org)
  • Zygosity is the degree of similarity of the alleles for a trait in an organism. (wikipedia.org)
  • haplotypes
  • When there are N {\displaystyle N} heterozygous genotypes present in an individual's set of genotypes, there will be 2 N {\displaystyle 2^{N}} possible pairs of haplotypes that could underlie the genotypes. (wikipedia.org)
  • The SHAPEIT1 method made a major advance by introducing a linear O ( K ) {\displaystyle O(K)} complexity method that operates only on the space of haplotypes consistent with an individual's genotypes. (wikipedia.org)
  • individuals
  • Here we consider the problem of using genotype data from a sample of individuals to distinguish between two forms of nonrandom mating: inbreeding or mating among relatives and population subdivision or limited dispersal of gametes. (genetics.org)
  • Therefore, considerable interest exists in the development of an approach that can reliably estimate the degree of population subdivision and inbreeding rates from a sample of genotyped individuals of unknown relatedness. (genetics.org)
  • which implements a Bayesian clustering algorithm that simultaneously estimates locus allele frequencies and probabilistically assigns individuals to one of K subpopulations. (genetics.org)
  • Individuals with two copies of 677C (677CC) have the most common genotype. (wikipedia.org)
  • 677TT individuals (homozygous) have lower MTHFR activity than CC or CT (heterozygous) individuals. (wikipedia.org)
  • Low folate intake affects individuals with the 677TT genotype to a greater extent than those with the 677CC/CT genotypes. (wikipedia.org)
  • In Rr individuals the R allele masks the presence of the r allele, so these individuals also have round peas. (wikipedia.org)
  • The frequency of "aa" individuals would increase until the abundance of the "a" resource begins to decline. (wikipedia.org)
  • Eventually, the "AA" and "aa" genotypes would reach equilibrium with each other, with "Aa" heterozygotic individuals potentially experiencing a reduced fitness compared to those individuals who are homozygotic for utilization of either resource. (wikipedia.org)
  • Curacao, however, which also has a significant population of individuals descending from African slaves, lacks the presence of widespread malaria, and therefore also lacks the selective pressure to maintain the HgbS allele. (wikipedia.org)
  • significantly
  • The plasma homocysteine levels in the patients with the TT genotype were not significantly higher than those in the patients with non-TT (CC+CT) genotypes (13.1±5.5 versus 11.5±3.1 mmol/L, P =0.16). (ahajournals.org)
  • Angiographic analysis showed that the percent diameter stenosis in the patients with the TT genotype was significantly greater than that in those with non-TT genotypes (43.7±17.8% versus 29.0±22.0%, P =0.015). (ahajournals.org)
  • Intravascular ultrasound analysis showed that the TT genotype was significantly associated with greater intimal hyperplasia area (5.70±1.94 versus 3.72±1.38 mm 2 , P =0.001). (ahajournals.org)
  • The heterozygous genotype was also significantly overexpressed in AMI patients and underexpressed in centenarians compared with young controls. (senescence.info)
  • In multiple sclerosis DQA1*0102 was the most frequent allele and DQB1*0602 increased significantly in the MS patients. (wikipedia.org)
  • In addition, the overall benefit of alleles is cut down significantly (by about half) by pleiotropy. (wikipedia.org)
  • equilibrium
  • This example of underdominance is stable because any shift in equilibrium would result in selection for the rare allele due to increased resource abundance. (wikipedia.org)
  • XX females and XY males, as in humans], f′(a) in the heterogametic sex 'chases' f(a) in the homogametic sex of the previous generation, until an equilibrium is reached at the weighted average of the two initial frequencies. (wikipedia.org)
  • substitution
  • The remainder of the equation, [ q ( W 2 − W 1 ) + p ( W 1 − W 0 ) ] {\displaystyle {\big [}q(W_{2}-W_{1})+p(W_{1}-W_{0}){\big ]}} , refers to the mean effect of an allele substitution. (wikipedia.org)
  • The 677T allele (leading to a valine substitution at amino acid 222) encodes a thermolabile enzyme with reduced activity. (wikipedia.org)
  • MTHFR
  • Methods and Results -To examine the potential influence of MTHFR genotype and homocysteine on coronary arteries morphologically, we screened 62 patients with 65 lesions that were treated with 93 Palmaz-Schatz stents. (ahajournals.org)
  • Primary GBMs with significant hypomethylation tended to be heterozygous or homozygous for the low-functioning Val allele of the rate-limiting methyl group metabolism gene methylenetetrahydrofolate reductase ( MTHFR ), or had a deletion encompassing this gene at 1p36. (aacrjournals.org)
  • species
  • This species possesses two alleles which each confer an appearance similar to that of another local butterfly species that is toxic to its predator. (wikipedia.org)
  • single
  • An extreme case of fitness that depends entirely on the mother's genotype at a single diallelic locus was considered by W right ( 1969 , pp. 57-59) and N agylaki ( 1992 ). (genetics.org)