Genes, fat intake, and cardiovascular disease risk factors in the Quebec family study

Objective: The aim of this study was to assess gene-diet interaction effects on cardiovascular disease (CVD) risk factors (waist circumference, plasma triacylglycerol, high-density lipoprotein-cholesterol and fasting glucose concentrations, and diastolic and systolic blood pressure) in the Quebec Family Study cohort. Design: Sixty-four polymorphisms from 45 candidate genes were studied in 645 subjects. Dietary fat intake was obtained from a 3-day weighted food record. Results: We observed 18 significant interactions at a p value <= 0.01. Among them, the Pro12A1a polymorphism in peroxisome proliferator-activated receptor gamma, alone or in interaction with fat intake, significantly modulated waist circumference (p = 0.0005 for both effects). Additionally, the apolipoprotein E genotype in interaction with fat intake was significantly associated with diastolic and systolic blood pressure (p = 0.01 and p = 0.001, respectively). The ghrelin Leu72Met polymorphism also interacted with dietary fat in its relation to waist circumference and triacylglycerol concentrations (p = 0.0004 and p = 0.005). Discussion: These results suggest that several alleles at candidate genes interact with dietary fat intake to modulate well-known CVD risk factors. The identification of gene-diet interaction effects is likely to provide useful information concerning the etiology of CVD.