Sentences with phrase «allele frequencies at»

Heterozygosity was determined from allele frequencies at genomic loci; the average number of alleles per locus was 6.45, with only 2.7 accounting for a majority of the diversity.

Adaptation in quantitative traits likely often occurs through subtle shifts in allele frequencies at many loci, a process called polygenic adaptation.

Not exact matches

In some cases, we can actually trace that increased risk to actual alleles that segregate at different frequencies in different populations (eg., diabetes in Native American populations).

The research by scientists at Children's Hospital Los Angeles and Columbia University shows a link between a particular allele for serotonin found at a higher frequency in those at risk of depression because of family history, and those who go on to develop major depressive disorder.

Instead, spontaneously transformed cells arose from the heterozygotes at a low frequency, and the majority of these cells had amplified the mutant allele.

Our approach differs from that adopted by Charlesworth [61], [62], who developed mathematical models to formalize the mutation accumulation hypothesis [63] that, together with the antagonistic pleiotropy hypothesis [3], [64], may be used to show how senescence can evolve by the accumulation of deleterious alleles through mutation - selection balance at frequencies that increase with their age of onset; such mutations enhance reproductive performance early in life but diminish survival late in life through physiological trade - offs.

In a sample with 26.9 % of CXCR4 alleles disrupted, NHEJ events were detected at a frequency of 2.3 % (170/7531 reads) in an extragenic region on chromosome 12 and 0.8 % (84 / 10531) in ADAMTS17, a metalloprotease of unknown function [45].

A similar pattern has been observed in humans, where alleles associated with lactase persistence in Europe did not rise to significant frequencies until at least the Bronze Age, that is, 3,000 years after the introduction of pastoral livestock35.

Double - strand validation was also used to check that the heteroplasmic alleles were present on both DNA strands at a frequency of at least 1 % [20, 38].

It follows from the last point above that the vast majority of common human genetic variation, i.e. SNPs with derived allele frequencies of at least 5 %, is neutral or nearly neutral with respect to fitness.

Results of this study has shown that there is a significant inter-population variability, as far as pharmacogenomic biomarker allele frequency is concerned, which has a direct impact on the rationalization of drug use at a population level.

However, most point mutations occur at low frequency, and the function of these alleles remains undefined.

Look at the allele frequency plot for the same chromosome offers some clarification:

We tested the hypothesis that the frequency of the minor Ser482 allele at the PPARGC1A locus is lower in World - class Spanish male endurance athletes (cases)[n = 104; mean (SD) age: 26.8 (3.8) yr] than in unfit United Kingdom (UK) Caucasian male controls [n = 100; mean (SD) age: 49.3 (8.1) yr].

Some of the associated variants were super rare (MAF < 1 %), suggesting that genotyping studies like this are well - powered to detect associations even at allele frequencies below one percent.

Not so long ago, there was a hope in the research community that common genetic variation, i.e. variants present at minor allele frequencies > 5 % in human populations, might explain most or all of the heritability of common complex disease.

Indeed, several admixture scenarios [44], [45] and selection at linked sites are expected to generate an excess of high frequency derived alleles, but the observation that most islands of differentiation are not enriched for high frequency derived alleles suggests that selection at linked sites is likely to have a relatively small contribution overall to the occurrence of areas of high differentiation.

They're not all rare variants, either: 86 million variants are classified as common (G5, G5A, or COMMON), with minor allele frequencies > 1 % in at least one population.

Thus, tumors with loss of heterozygosity (LOH) at 9p21 - the chromosomal location of p16 - should have a high frequency of intragenic mutations in the other allele that block gene function.

The strongest signal of selection is at the allele responsible for lactase persistence, supporting the view that an appreciable frequency of lactase persistence in Europe only dates to the past four thousand years.

The polyT repeat in intron 6 of TOMM40 (rs10524523) was genotyped using fluorescence - based fragment size analysis (Supplemental Figure 1; http://neuroscienceresearch.wustl.edu/pages/cruchaga2011.aspx).19 A detailed explanation of the fluorescence - based fragment size genotyping, quality control steps, allele frequency, and linkage disequilibrium between the studied polymorphisms can be found at http://neuroscienceresearch.wustl.edu/Pages/cruchaga2011.aspx.

Some of the earliest studies of cancer genomes in AML noted that, within a single patient, there were subsets of mutations present at lower allele frequencies, suggesting that they're not present in all cells.

Tumor content was estimated at greater than 60 % by histopathologic review of tumor sections (Fig. 1B) and variant allele frequency analysis.

We performed two statistical analyses to support the genetic evidence that indels at this locus, including those observed at low frequency in cfDNA, were likely to represent bona fide reversion alleles.

Two novel cardiometabolic associations are at lead variants unique to the founder population sequences: chr16: 70790626 (high - density lipoprotein levels beta -1.71 (SE 0.25), P = 1.57 × 10 ^-11 , effect allele frequency (EAF) 0.006); and rs145556679 (triglycerides levels beta -1.13 (SE 0.17), P = 2.53 × 10 ^-11 , EAF 0.013).

A genome - wide FST scan comparison with previous sequence data from an area in West Africa with higher infection endemicity indicates that regional gene flow prevents genetic isolation, but revealed allele frequency differentiation at three drug resistance loci and an erythrocyte invasion ligand gene.

Conversely, in both Eastern and Southwestern regions the Vgsc - 1014F alleles were close to fixation, whilst Ace1 - 119S allele frequency was 12 % (although frequencies may be underestimated due to copy number variation at both loci).

For each of the three genes, one allele (variant) is found at unusually high frequency in dogs that have been treated for bloat, and the presence of any one of these «risk» alleles triples the chance that the dog will experience bloat at some time in its life.

The latter estimate is made by adjusting the frequencies of alleles found at each genomic STR locus to the frequency of the same allele in a large population of random breeding village dogs, thus yielding IR - village dog (IRVD).

Six of 33 loci had an allele with frequency > 70 %, and allele 202 at locus REN162C04 was homozygous in 101/102 dogs studied.

Doing a genetic test and subsequently eliminating an individual from the breeding population may not be the best strategy, as by targeting a particular allele at one genetic locus for removal from the gene pool of a particular breed, breeders may in fact increase allele frequency of genetic variants on alternative haplotypes at the same, or a different locus, that are recessively deleterious.

When a breed population carries a high frequency for a known detrimental allele at a specific genetic locus, it may be possible to crossbreed with an animal free of the detrimental allele and then backcross to the original lineage, monitoring the presence of the desired allele using genetic testing.

Although not balanced in frequency, genetic assessment of the seven STR alleles associated with the DLA class I and II regions showed them to be randomly segregating at this time.

The larger and more numerous these regions, the more often they will be associated with an STR and the more likely that certain STR alleles will be at higher frequency and also exist in a homozygous state.

Flat prior distributions were defined for the nongenetic effects and effects at the single locus (− ∞, ∞), for the variance components (0, ∞), and for the allele frequencies (0,1).

Please note... there is no estimate of the frequency of the false allele at this time, although it is much lower with the recently improved tests.

It is fixed in the Dalmatian breed and occurs at high allele frequency in the Bulldog and Black Russian Terrier breeds [29].

At the present time, an insufficient number of the countries from this correlation are represented in the genetic databases [e.g. HapMap (International HapMap Consortium, 2005) and Human Genome Diversity Panel (Li et al., 2008)-RSB- to determine if the present results are significantly different from the frequency distribution of randomly selected alleles from representatives of each of these countries.