Chinese Han Population Agtr1 Gene And Association Studies Of Myocardial Infarction In The Choice Of Tagging The Snp And Haplotype Analysis

BackgroundThe renin-angiotensin system (RAS) is implicated in the pathogenesis of hypertension, cardiac hypertrophy and coronary heart disease. The major biologically active product of the RAS is angiotensin II (ANG II), a peptide with multiple functions, including vasoconstriction, aldosterone production, hypertrophic and hyperplastic effects on vascular smooth muscle cells and cardiomyocytes, and synthesis of the extracellular collagen matrix. In adult humans, the effects of ANG II are mainly mediated by the angiotensin II type 1 receptor (AT1R). Because of the physiological role of this receptor, the AT1R gene (AGTR1) has been a candidate gene for hypertension and coronary heart disease. The contributions of variants of AGTR1 gene to cardiovascular diseases are conflicted in previous reports. In the present study, a multi-step case-control study was designed for evaluating the contribution of AGTR1 variations to myocardial infarction (MI) in Chinese Han population. We first scanned the AGTR1 gene to identify all putative functional polymorphisms within a sub-sample. The pattern of linkage disequilibrium across the whole gene was characterized and tSNPs were selected. Then these tSNPs were further genotyped in the entire study population. Both locus-based and haplotype-based association tests were used to evaluate the possible effect of AGTR1 gene on MI.MethodsA total of 419 males who survived an acute MI were eligible for this study. They were enrolled from Fu Wai Hospital & Cardiovascular Institute (Beijing, China) between October 1997 and September 2000. Diagnoses of all cases in this study follow strict diagnostic rules based on signs, symptoms, electrocardiograms and cardiac enzymes. Subjects with congenital heart disease, cardiomyopathy, valvular disease, and renal or hepatic disease were excluded. Age-matched (± 2 years) male...