Association between PPARα gene polymorphisms and myocardial infarction

PPARα (peroxisome-proliferator-activated receptor α) regulates the expression of genes that are involved in lipid metabolism, tissue homoeostasis and inflammation. Consistent rodent and human studies suggest a link between PPARα function and cardiovascular disease, qualifying PPARα [PPARA in HUGO (Human Genome Organisation) gene nomenclature] as a candidate gene for coronary artery disease. In the present study, we comprehensively evaluated common genetic variations within the PPARα gene and assessed their association with myocardial infarction. First, we characterized the linkage disequilibrium within the PPARα gene in an initial case-control sample of 806 individuals from the Regensburg Myocardial Infarction Family Study using a panel of densely spaced SNPs (single nucleotide polymorphisms) across the gene. Single SNP analysis showed significant association with the disease phenotype [OR (odds ratio) = 0.74, P = 0.012, 95% CI (confidence interval) = 0.61-0.94 for rsl 3555l]. Moreover, we identified a protective three-marker haplotype with an association trend for myocardial infarction (OR = 0.76, P = 0.067, 95 % CI = 0.56-1.02). Subsequently, we were able to confirm the single SNP and haplotype association results in an independent second case-control cohort with 667 cases from the Regensburg Myocardial Infarction Family Study and 862 control individuals from the WHO (World Health Organization) MONICA (Monitoring of Trends and Determinants in Cardiovascular Disease) Augsburg project (OR = 0.87, P = 0.046, 95% CI = 0.72-0.99 for rsl3555l and OR = 0.80, P = 0.034, 95 % CI = 0.65-0.98 for the three-marker haplotype respectively). From these cross-sectional association results, we provide evidence that common variations in the PPARα gene may influence the risk of myocardial infarction in a European population.