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排序方式： 共有159条查询结果，搜索用时 15 毫秒
1.
Maria D. Jackson Marshall K. Tulloch-Reid Norma McFarlane-Anderson Alexis Watson Vestra Seers Franklyn I. Bennett Brian Egleston Camille Ragin 《Genes & nutrition》2013,8(2):199-207
Little is known about the role of folate and polymorphisms associated with folate metabolism on prostate cancer risk in populations of African origin. We examined the relationship between serum folate and prostate cancer and whether any association was modified by genetic polymorphisms for folate metabolism. The study was case–control in design and consisted of 218 men 40–80 years old with newly diagnosed, histologically confirmed prostate cancer and 236 cancer-free men attending the same urology clinics in Jamaica, March 2005–July 2007. Serum folate was measured by an immunoassay method and genomic DNA evaluated for MTHR (C677T and A1298C), MTRR A66G, and MTR A2756G polymorphisms. Mean serum folate concentration was higher among cases (12.3 ± 4.1 nmol/L) than controls (9.7 ± 4.2 nmol/L). Serum folate concentration showed a positive association with prostate cancer (OR, 4.41; CI, 2.52–7.72 per 10 nmol/L) regardless of grade. No interactions were observed between genotype and folate concentration, but a weak gene effect was observed for MTHFR A1298C and low-grade prostate cancer. Larger studies to investigate the role of gene–gene/gene–diet interactions in Black men are needed. 相似文献
2.
Elizabeth G. Mandeville Thomas L. Parchman David B. McDonald C. Alex Buerkle 《Molecular ecology》2015,24(8):1856-1872
Hybridization between diverged taxa tests the strength of reproductive isolation and can therefore reveal mechanisms of reproductive isolation. However, it remains unclear how consistent reproductive isolation is across species' ranges and to what extent reproductive isolation might remain polymorphic as species diverge. To address these questions, we compared outcomes of hybridization across species pairs of Catostomus fishes in three rivers in the Upper Colorado River basin, where an introduced species, C. commersoni, hybridizes with at least two native species, C. discobolus and C. latipinnis. We observed substantial heterogeneity in outcomes of hybridization, both between species pairs and across geographically separate rivers within each species pair. We also observed hybridization of additional related species with our focal species, suggesting that reproductive isolation in this group involves interactions of multiple evolutionary and ecological factors. These findings suggest that a better understanding of the determinants of variation in reproductive isolation is needed and that studies of reproductive isolation in hybrids should consider how the dynamics and mechanisms of reproductive isolation vary over ecological space and over evolutionary time. Our results also have implications for the conservation and management of native catostomids in the Colorado River basin. Heterogeneity in outcomes of hybridization suggests that the threat posed by hybridization and genetic introgression to the persistence of native species probably varies with extent of reproductive isolation, both across rivers and across species pairs. 相似文献
3.
Leslie A. Brick Matthew C. Keller Valerie S. Knopik John E. McGeary Rohan H.C. Palmer 《Addiction biology》2019,24(1):132-144
Alcohol dependence (AD) affects individuals from all racial/ethnic groups, and previous research suggests that there is considerable variation in AD risk between and among various ancestrally defined groups in the United States. Although the reasons for these differences are likely due in part to contributions of complex sociocultural factors, limited research has attempted to examine whether similar genetic variation plays a role across ancestral groups. Using a pooled sample of individuals of African and European ancestry (AA/EA) obtained through data shared within the Database for Genotypes and Phenotypes, we estimated the extent to which additive genetic similarity for AD between AA and EAs using common single nucleotide polymorphisms overlapped across the two populations. AD was represented as a factor score by using Diagnostic and Statistical Manual dependence criteria, and genetic data were imputed by using the 1000 Genomes Reference Panel. Analyses revealed a significant single nucleotide polymorphism‐based heritability of 17 percent (SE = 5) in EAs and 24 percent (SE = 15) in AAs. Further, a significant genetic correlation of 0.77 (SE = 0.46) suggests that the allelic architecture influencing the AD factor for EAs and AAs is largely similar across the two populations. Analyses indicated that investigating the genetic underpinnings of alcohol dependence in different ethnic groups may serve to highlight core etiological factors common to both groups and unique etiological factors specific to each ethnic group. 相似文献
4.
5.
《American journal of human genetics》2023,110(6):927-939
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6.
Alina Schenk Saioa Lpez Maik Kschischo Nicholas McGranahan 《Evolutionary Applications》2020,13(7):1550-1557
Precision medicine relies on targeting specific somatic alterations present in a patient's tumor. However, the extent to which germline ancestry may influence the somatic burden of disease has received little attention. We estimated the genetic ancestry of non‐small‐cell lung cancer (NSCLC) patients and performed an in‐depth analysis of the influence of genetic ancestry on the evolutionary disease course. Compared with European Americans (EA), African Americans (AA) with lung adenocarcinoma (LUAD) were found to be significantly younger and smoke significantly less. However, LUADs from AAs exhibited a significantly higher somatic mutation burden, with a more pronounced tobacco carcinogen footprint and increased frequencies of alterations affecting cancer genes. Conversely, no significant differences were observed between lung squamous cell carcinomas (LUSC) from EAs and AAs. Our results suggest germline ancestry influences the somatic evolution of LUAD but not LUSC. 相似文献
7.
《Evolutionary Applications》2018,11(5):662-680
Hybridisation between a domesticated species and its wild ancestor is an important conservation problem, especially if it results in the introgression of domestic gene variants into wild species. Nevertheless, the legal status of hybrids remains unregulated, partially because of the limited understanding of the hybridisation process and its consequences. The occurrence of hybridisation between grey wolves and domestic dogs is well documented from different parts of the wolf geographic range, but little is known about the frequency of hybridisation events, their causes and the genetic impact on wolf populations. We analysed 61K SNPs spanning the canid genome in wolves from across Eurasia and North America and compared that data to similar data from dogs to identify signatures of admixture. The haplotype block analysis, which included 38 autosomes and the X chromosome, indicated the presence of individuals of mixed wolf–dog ancestry in most Eurasian wolf populations, but less admixture was present in North American populations. We found evidence for male‐biased introgression of dog alleles into wolf populations, but also identified a first‐generation hybrid resulting from mating between a female dog and a male wolf. We found small blocks of dog ancestry in the genomes of 62% Eurasian wolves studied and melanistic individuals with no signs of recent admixed ancestry, but with a dog‐derived allele at a locus linked to melanism. Consequently, these results suggest that hybridisation has been occurring in different parts of Eurasia on multiple timescales and is not solely a recent phenomenon. Nevertheless, wolf populations have maintained genetic differentiation from dogs, suggesting that hybridisation at a low frequency does not diminish distinctiveness of the wolf gene pool. However, increased hybridisation frequency may be detrimental for wolf populations, stressing the need for genetic monitoring to assess the frequency and distribution of individuals resulting from recent admixture. 相似文献
8.
《Addiction biology》2017,22(2):535-549
Outcomes related to disordered metabolism are common in alcohol dependence (AD). To investigate alterations in the regulation of body mass that occur in the context of AD, we performed a genome‐wide association study (GWAS) of body mass index (BMI) in African Americans (AAs) and European Americans (EAs) with AD. Subjects were recruited for genetic studies of AD or drug dependence and evaluated using the Semi‐structured Assessment for Drug Dependence and Alcoholism. We investigated a total of 2587 AAs and 2959 EAs with DSM‐IV AD diagnosis. In the stage 1 sample (N = 4137), we observed three genome‐wide significant (GWS) single‐nucleotide polymorphism associations, rs200889048 (P = 8.98 * 10−12) and rs12490016 (P = 1.44 * 10−8) in EAs and rs1630623 (P = 5.14 * 10−9) in AAs and EAs meta‐analyzed. In the stage 2 sample (N = 1409), we replicated 278, 253 and 168 of the stage 1 suggestive loci (P < 5*10−4) in AAs, EAs, and AAs and EAs meta‐analyzed, respectively. A meta‐analysis of stage 1 and stage 2 samples (N = 5546) identified two additional GWS signals: rs28562191 in EAs (P = 4.46 * 10−8) and rs56950471 in AAs (P = 1.57 * 10−9). Three of the GWS loci identified (rs200889048, rs12490016 and rs1630623) were not previously reported by GWAS of BMI in the general population, and two of them raise interesting hypotheses: rs12490016—a regulatory variant located within LINC00880, where there are other GWAS‐identified variants associated with birth size, adiposity in newborns and bulimia symptoms, which also interact with social stress in relation to birth size; rs1630623—a regulatory variant related to ALDH1A1, a gene involved in alcohol metabolism and adipocyte plasticity. These loci offer molecular insights regarding the regulatory mechanisms of body mass in the context of AD. 相似文献
9.
Ahmed El‐Boraie Taraneh Taghavi Meghan J. Chenoweth Koya Fukunaga Taisei Mushiroda Michiaki Kubo Caryn Lerman Nicole L. Nollen Neal L. Benowitz Rachel F. Tyndale 《Addiction biology》2020,25(1)
The nicotine metabolite ratio (NMR; 3‐hydroxycotinine/cotinine) is an index of CYP2A6 activity. CYP2A6 is responsible for nicotine's metabolic inactivation and variation in the NMR/CYP2A6 is associated with several smoking behaviors. Our aim was to integrate established alleles and novel genome‐wide association studies (GWAS) signals to create a weighted genetic risk score (wGRS) for the CYP2A6 gene for European‐ancestry populations. The wGRS was compared with a previous CYP2A6 gene scoring approach designed for an alternative phenotype (C2/N2; cotinine‐d2/(nicotine‐d2 + cotinine‐d2)). CYP2A6 genotypes and the NMR were assessed in European‐ancestry participants. The wGRS training set included N = 933 smokers recruited to the Pharmacogenetics of Nicotine Addiction and Treatment clinical trial [NCT01314001]. The replication cohort included N = 196 smokers recruited to the Quit 2 Live clinical trial [NCT01836276]. Comparisons between the two CYP2A6 phenotypes and with fractional clearance were made in a laboratory‐based pharmacokinetic study (N = 92 participants). In both the training and replication sets, the wGRS, which included seven CYP2A6 variants, explained 33.8% (P < 0.001) of the variance in NMR, providing improved predictive power to the NMR phenotype when compared with other CYP2A6 gene scoring approaches. NMR and C2/N2 were strongly correlated to nicotine clearance (ρ = 0.70 and ρ = 0.79, respectively; P < 0.001), and to one another (ρ = 0.82; P < 0.001); however reduced function genotypes occurred in slow NMR but throughout C2/N2. The wGRS was able to predict smoking quantity and nicotine intake, to discriminate between NMR slow and normal metabolizers (AUC = 0.79; P < 0.001), and to replicate previous NMR‐stratified cessation outcomes showing unique treatment outcomes between metabolizer groups. 相似文献
10.
