@article {817, title = {Population structure, admixture, and aging-related phenotypes in African American adults: the Cardiovascular Health Study.}, journal = {Am J Hum Genet}, volume = {76}, year = {2005}, month = {2005 Mar}, pages = {463-77}, abstract = {

U.S. populations are genetically admixed, but surprisingly little empirical data exists documenting the impact of such heterogeneity on type I and type II error in genetic-association studies of unrelated individuals. By applying several complementary analytical techniques, we characterize genetic background heterogeneity among 810 self-identified African American subjects sampled as part of a multisite cohort study of cardiovascular disease in older adults. On the basis of the typing of 24 ancestry-informative biallelic single-nucleotide-polymorphism markers, there was evidence of substantial population substructure and admixture. We used an allele-sharing-based clustering algorithm to infer evidence for four genetically distinct subpopulations. Using multivariable regression models, we demonstrate the complex interplay of genetic and socioeconomic factors on quantitative phenotypes related to cardiovascular disease and aging. Blood glucose level correlated with individual African ancestry, whereas body mass index was associated more strongly with genetic similarity. Blood pressure, HDL cholesterol level, C-reactive protein level, and carotid wall thickness were not associated with genetic background. Blood pressure and HDL cholesterol level varied by geographic site, whereas C-reactive protein level differed by occupation. Both ancestry and genetic similarity predicted the number and quality of years lived during follow-up, but socioeconomic factors largely accounted for these associations. When the 24 genetic markers were tested individually, there were an excess number of marker-trait associations, most of which were attenuated by adjustment for genetic ancestry. We conclude that the genetic demography underlying older individuals who self identify as African American is complex, and that controlling for both genetic admixture and socioeconomic characteristics will be required in assessing genetic associations with chronic-disease-related traits in African Americans. Complementary methods that identify discrete subgroups on the basis of genetic similarity may help to further characterize the complex biodemographic structure of human populations.

}, keywords = {African Americans, Aged, Aging, Algorithms, Cardiovascular Diseases, Cohort Studies, Female, Genetics, Population, Genotype, Humans, Male, Models, Genetic, Phenotype, Polymorphism, Single Nucleotide, Quantitative Trait Loci, Risk Factors, Socioeconomic Factors}, issn = {0002-9297}, doi = {10.1086/428654}, author = {Reiner, Alexander P and Ziv, Elad and Lind, Denise L and Nievergelt, Caroline M and Schork, Nicholas J and Cummings, Steven R and Phong, Angie and Burchard, Esteban Gonz{\'a}lez and Harris, Tamara B and Psaty, Bruce M and Kwok, Pui-Yan} } @article {986, title = {Common variants in the CRP gene in relation to longevity and cause-specific mortality in older adults: the Cardiovascular Health Study.}, journal = {Atherosclerosis}, volume = {197}, year = {2008}, month = {2008 Apr}, pages = {922-30}, abstract = {

Common polymorphisms in the CRP gene are associated with plasma CRP levels in population-based studies, but associations with age-related events are uncertain. A previous study of CRP haplotypes in older adults was broadened to include longevity and cause-specific mortality (all-cause, noncardiovascular (non-CV), and cardiovascular (CV)). Common haplotypes were inferred from four tagSNPs in 4512 whites and five tagSNPs in 812 blacks from the Cardiovascular Health Study, a longitudinal cohort of adults over age 65. Exploratory analyses addressed early versus late mortality. CRP haplotypes were not associated with all-cause mortality or longevity overall in either population, but associations with all-cause mortality differed during early and late periods. In blacks, the haplotype tagged by 3872A (rs1205) was associated with increased risk of non-CV mortality, relative to other haplotypes (adjusted hazard ratio for each additional copy: 1.42, 95\% CI: 1.07, 1.87). Relative to other haplotypes, this haplotype was associated with decreased risk of early but not decreased risk of late CV mortality in blacks; among whites, a haplotype tagged by 2667C (rs1800947) gave similar but nonsignificant findings. If confirmed, CRP genetic variants may be weakly associated with CV and non-CV mortality in older adults, particularly in self-identified blacks.

}, keywords = {African Americans, Aged, C-Reactive Protein, Cardiovascular Diseases, Cause of Death, Cohort Studies, Female, Genetic Predisposition to Disease, Haplotypes, Humans, Linear Models, Longevity, Male, Polymorphism, Single Nucleotide, Proportional Hazards Models, United States}, issn = {1879-1484}, doi = {10.1016/j.atherosclerosis.2007.08.012}, author = {Hindorff, Lucia A and Rice, Kenneth M and Lange, Leslie A and Diehr, Paula and Halder, Indrani and Walston, Jeremy and Kwok, Pui and Ziv, Elad and Nievergelt, Caroline and Cummings, Steven R and Newman, Anne B and Tracy, Russell P and Psaty, Bruce M and Reiner, Alexander P} } @article {6585, title = {Meta-analysis of genome-wide association studies in African Americans provides insights into the genetic architecture of type 2 diabetes.}, journal = {PLoS Genet}, volume = {10}, year = {2014}, month = {2014 Aug}, pages = {e1004517}, abstract = {

Type 2 diabetes (T2D) is more prevalent in African Americans than in Europeans. However, little is known about the genetic risk in African Americans despite the recent identification of more than 70 T2D loci primarily by genome-wide association studies (GWAS) in individuals of European ancestry. In order to investigate the genetic architecture of T2D in African Americans, the MEta-analysis of type 2 DIabetes in African Americans (MEDIA) Consortium examined 17 GWAS on T2D comprising 8,284 cases and 15,543 controls in African Americans in stage 1 analysis. Single nucleotide polymorphisms (SNPs) association analysis was conducted in each study under the additive model after adjustment for age, sex, study site, and principal components. Meta-analysis of approximately 2.6 million genotyped and imputed SNPs in all studies was conducted using an inverse variance-weighted fixed effect model. Replications were performed to follow up 21 loci in up to 6,061 cases and 5,483 controls in African Americans, and 8,130 cases and 38,987 controls of European ancestry. We identified three known loci (TCF7L2, HMGA2 and KCNQ1) and two novel loci (HLA-B and INS-IGF2) at genome-wide significance (4.15 {\texttimes} 10(-94)}, keywords = {African Americans, Diabetes Mellitus, Type 2, Genome-Wide Association Study, HLA-B27 Antigen, HMGA2 Protein, Humans, KCNQ1 Potassium Channel, Mutant Chimeric Proteins, Polymorphism, Single Nucleotide, Transcription Factor 7-Like 2 Protein}, issn = {1553-7404}, doi = {10.1371/journal.pgen.1004517}, author = {Ng, Maggie C Y and Shriner, Daniel and Chen, Brian H and Li, Jiang and Chen, Wei-Min and Guo, Xiuqing and Liu, Jiankang and Bielinski, Suzette J and Yanek, Lisa R and Nalls, Michael A and Comeau, Mary E and Rasmussen-Torvik, Laura J and Jensen, Richard A and Evans, Daniel S and Sun, Yan V and An, Ping and Patel, Sanjay R and Lu, Yingchang and Long, Jirong and Armstrong, Loren L and Wagenknecht, Lynne and Yang, Lingyao and Snively, Beverly M and Palmer, Nicholette D and Mudgal, Poorva and Langefeld, Carl D and Keene, Keith L and Freedman, Barry I and Mychaleckyj, Josyf C and Nayak, Uma and Raffel, Leslie J and Goodarzi, Mark O and Chen, Y-D Ida and Taylor, Herman A and Correa, Adolfo and Sims, Mario and Couper, David and Pankow, James S and Boerwinkle, Eric and Adeyemo, Adebowale and Doumatey, Ayo and Chen, Guanjie and Mathias, Rasika A and Vaidya, Dhananjay and Singleton, Andrew B and Zonderman, Alan B and Igo, Robert P and Sedor, John R and Kabagambe, Edmond K and Siscovick, David S and McKnight, Barbara and Rice, Kenneth and Liu, Yongmei and Hsueh, Wen-Chi and Zhao, Wei and Bielak, Lawrence F and Kraja, Aldi and Province, Michael A and Bottinger, Erwin P and Gottesman, Omri and Cai, Qiuyin and Zheng, Wei and Blot, William J and Lowe, William L and Pacheco, Jennifer A and Crawford, Dana C and Grundberg, Elin and Rich, Stephen S and Hayes, M Geoffrey and Shu, Xiao-Ou and Loos, Ruth J F and Borecki, Ingrid B and Peyser, Patricia A and Cummings, Steven R and Psaty, Bruce M and Fornage, Myriam and Iyengar, Sudha K and Evans, Michele K and Becker, Diane M and Kao, W H Linda and Wilson, James G and Rotter, Jerome I and Sale, Mich{\`e}le M and Liu, Simin and Rotimi, Charles N and Bowden, Donald W} } @article {6875, title = {Drug-Gene Interactions of Antihypertensive Medications and Risk of Incident Cardiovascular Disease: A Pharmacogenomics Study from the CHARGE Consortium.}, journal = {PLoS One}, volume = {10}, year = {2015}, month = {2015}, pages = {e0140496}, abstract = {

BACKGROUND: Hypertension is a major risk factor for a spectrum of cardiovascular diseases (CVD), including myocardial infarction, sudden death, and stroke. In the US, over 65 million people have high blood pressure and a large proportion of these individuals are prescribed antihypertensive medications. Although large long-term clinical trials conducted in the last several decades have identified a number of effective antihypertensive treatments that reduce the risk of future clinical complications, responses to therapy and protection from cardiovascular events vary among individuals.

METHODS: Using a genome-wide association study among 21,267 participants with pharmaceutically treated hypertension, we explored the hypothesis that genetic variants might influence or modify the effectiveness of common antihypertensive therapies on the risk of major cardiovascular outcomes. The classes of drug treatments included angiotensin-converting enzyme inhibitors, beta-blockers, calcium channel blockers, and diuretics. In the setting of the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium, each study performed array-based genome-wide genotyping, imputed to HapMap Phase II reference panels, and used additive genetic models in proportional hazards or logistic regression models to evaluate drug-gene interactions for each of four therapeutic drug classes. We used meta-analysis to combine study-specific interaction estimates for approximately 2 million single nucleotide polymorphisms (SNPs) in a discovery analysis among 15,375 European Ancestry participants (3,527 CVD cases) with targeted follow-up in a case-only study of 1,751 European Ancestry GenHAT participants as well as among 4,141 African-Americans (1,267 CVD cases).

RESULTS: Although drug-SNP interactions were biologically plausible, exposures and outcomes were well measured, and power was sufficient to detect modest interactions, we did not identify any statistically significant interactions from the four antihypertensive therapy meta-analyses (Pinteraction > 5.0{\texttimes}10-8). Similarly, findings were null for meta-analyses restricted to 66 SNPs with significant main effects on coronary artery disease or blood pressure from large published genome-wide association studies (Pinteraction >= 0.01). Our results suggest that there are no major pharmacogenetic influences of common SNPs on the relationship between blood pressure medications and the risk of incident CVD.

}, keywords = {African Americans, Aged, Antihypertensive Agents, Cardiovascular Diseases, European Continental Ancestry Group, Female, Genome-Wide Association Study, Humans, Hypertension, Incidence, Male, Middle Aged, Polymorphism, Single Nucleotide, Treatment Outcome}, issn = {1932-6203}, doi = {10.1371/journal.pone.0140496}, author = {Bis, Joshua C and Sitlani, Colleen and Irvin, Ryan and Avery, Christy L and Smith, Albert Vernon and Sun, Fangui and Evans, Daniel S and Musani, Solomon K and Li, Xiaohui and Trompet, Stella and Krijthe, Bouwe P and Harris, Tamara B and Quibrera, P Miguel and Brody, Jennifer A and Demissie, Serkalem and Davis, Barry R and Wiggins, Kerri L and Tranah, Gregory J and Lange, Leslie A and Sotoodehnia, Nona and Stott, David J and Franco, Oscar H and Launer, Lenore J and St{\"u}rmer, Til and Taylor, Kent D and Cupples, L Adrienne and Eckfeldt, John H and Smith, Nicholas L and Liu, Yongmei and Wilson, James G and Heckbert, Susan R and Buckley, Brendan M and Ikram, M Arfan and Boerwinkle, Eric and Chen, Yii-Der Ida and de Craen, Anton J M and Uitterlinden, Andr{\'e} G and Rotter, Jerome I and Ford, Ian and Hofman, Albert and Sattar, Naveed and Slagboom, P Eline and Westendorp, Rudi G J and Gudnason, Vilmundur and Vasan, Ramachandran S and Lumley, Thomas and Cummings, Steven R and Taylor, Herman A and Post, Wendy and Jukema, J Wouter and Stricker, Bruno H and Whitsel, Eric A and Psaty, Bruce M and Arnett, Donna} }