Search results for "polymorph"
showing 10 items of 2115 documents
Y-SNPs Do Not Indicate Hybridisation between European Aurochs and Domestic Cattle
2008
BackgroundPrevious genetic studies of modern and ancient mitochondrial DNA have confirmed the Near Eastern origin of early European domestic cattle. However, these studies were not able to test whether hybridisation with male aurochs occurred post-domestication. To address this issue, Götherström and colleagues (2005) investigated the frequencies of two Y-chromosomal haplotypes in extant bulls. They found a significant influence of wild aurochs males on domestic populations thus challenging the common view on early domestication and Neolithic stock-rearing. To test their hypothesis, we applied these Y-markers on Neolithic bone specimens from various European archaeological sites.Methods and…
Colour polymorphism torn apart by opposing positive frequency-dependent selection, yet maintained in space.
2015
Summary Polymorphic warning signals in aposematic species are enigmatic because predator learning and discrimination should select for the most common coloration, resulting in positive frequency‐dependent survival selection. Here, we investigated whether differential mating success could create sufficiently strong negative frequency‐dependent selection for rare morphs to explain polymorphic (white and yellow) warning coloration in male wood tiger moths (Parasemia plantaginis). We conducted an experiment in semi‐natural conditions where we estimated mating success for both white and yellow male moths under three different morph frequencies. Contrary to expectations, mating success was positi…
Comprehensive exploration of the effects of miRNA SNPs on monocyte gene expression.
2012
We aimed to assess whether pri-miRNA SNPs (miSNPs) could influence monocyte gene expression, either through marginal association or by interacting with polymorphisms located in 3'UTR regions (3utrSNPs). We then conducted a genome-wide search for marginal miSNPs effects and pairwise miSNPs × 3utrSNPs interactions in a sample of 1,467 individuals for which genome-wide monocyte expression and genotype data were available. Statistical associations that survived multiple testing correction were tested for replication in an independent sample of 758 individuals with both monocyte gene expression and genotype data. In both studies, the hsa-mir-1279 rs1463335 was found to modulate in cis the expres…
Novel loci for childhood body mass index and shared heritability with adult cardiometabolic traits
2020
The genetic background of childhood body mass index (BMI), and the extent to which the well-known associations of childhood BMI with adult diseases are explained by shared genetic factors, are largely unknown. We performed a genome-wide association study meta-analysis of BMI in 61,111 children aged between 2 and 10 years. Twenty-five independent loci reached genome-wide significance in the combined discovery and replication analyses. Two of these, located nearNEDD4LandSLC45A3, have not previously been reported in relation to either childhood or adult BMI. Positive genetic correlations of childhood BMI with birth weight and adult BMI, waist-to-hip ratio, diastolic blood pressure and type 2 d…
A high-density SNP linkage scan with 142 combined subtype ADHD sib pairs identifies linkage regions on chromosomes 9 and 16
2008
As part of the International Multi-centre ADHD Gene (IMAGE) project we have completed an affected sibling pair study of 142 narrowly defined DSM-IV combined type ADHD proband-sibling pairs. We found suggestive linkage on chromosomes 9 and 16 with non-parametric multipoint peak LOD scores of 2.13 and 3.1 respectively. There have been several previous ADHD linkage scans. The UCLA study (Fisher et al. 2002; Ogdie et al. 2004; Ogdie et al. 2003), the Dutch study (Bakker et al. 2003), the German study (Hebebrand et al. 2006) and the MGH Study (Faraone et al., submitted) applied the affected sib pair (ASP) strategy; the Columbian study used extended pedigrees ascertained from a population isolate…
Genetic control of male cuticular hydrocarbons in Drosophila melanogaster
1996
0016-6723 (Print) Comparative Study Journal Article; 7-tricosene (7-T) and 7-pentacosene (7-P) are the two main hydrocarbons on the cuticle of male Drosophila melanogaster. These two substances might play a pheromonal role during courtship behaviour. We investigated the genetic basis of the quantitative polymorphism observed in the production of 7-T and 7-P. Strains of different geographic origin, with males producing either predominantly 7-T or predominantly 7-P, were hybridized with strains carrying genetic markers. We found that chromosome II changes the balance between 7-T and 7-P while chromosome III regulates the overall quantity of both 7-monoenes. We have also characterized and roug…
Sex-specific association of the ST8SIAII gene with schizophrenia in a Spanish population
2013
We investigated the association between ST8SIAII and schizophrenia in a sample of Spanish origin. We found that the G allele (P=0.044) and the AG genotype (P=0.040) of rs3759916 were associated in females. The ACAG haplotype (rs3759914, rs3759915, rs3759916 and rs2305561) was associated in males (P=0.028).
PAH gene mutations in the Sicilian population: association with minihaplotypes and expression analysis.
2001
Abstract The molecular basis of PAH deficiency in the Sicilian population is characterized by a marked heterogeneity, with 44 mutations at a single locus identified by a "gene-scanning" approach and accounting for a detection rate of 91%. The remaining 9% of PAH alleles does not bear mutations in any of the 13 exons and 24 exon/intron junctions. Three mutations IVS10nt-11 G > A, R261Q, and A300S accounted for 30.5%, whereas the remaining mutations were found at relative frequencies of less than 5% and 20 mutations were observed once only. Five mutations have been detected only in Sicilians so far. By studying the association of mutations with intragenic STR-VNTR haplotypes ("minihaplotypes"…
Bayesian model to detect phenotype-specific genes for copy number data
2012
Abstract Background An important question in genetic studies is to determine those genetic variants, in particular CNVs, that are specific to different groups of individuals. This could help in elucidating differences in disease predisposition and response to pharmaceutical treatments. We propose a Bayesian model designed to analyze thousands of copy number variants (CNVs) where only few of them are expected to be associated with a specific phenotype. Results The model is illustrated by analyzing three major human groups belonging to HapMap data. We also show how the model can be used to determine specific CNVs related to response to treatment in patients diagnosed with ovarian cancer. The …
Assessment of Susceptibility Risk Factors for ADHD in Imaging Genetic Studies
2019
Objective: ADHD consists of a count of symptoms that often presents heterogeneity due to overdispersion and excess of zeros. Statistical inference is usually based on a dichotomous outcome that is underpowered. The main goal of this study was to determine a suited probability distribution to analyze ADHD symptoms in Imaging Genetic studies. Method: We used two independent population samples of children to evaluate the consistency of the standard probability distributions based on count data for describing ADHD symptoms. Results: We showed that the zero-inflated negative binomial (ZINB) distribution provided the best power for modeling ADHD symptoms. ZINB reveals a genetic variant, rs273342…