Background and objective: The aims of the GEMM Family Study are to clarify the genetic determinants of cardiovascular disease (CVD) risk in individuals born and living in Mexico. The authors evaluate the heritabilities (h2) of CVD risk factors in Mexicans from a preliminary cohort already studied. Heritabilities for CVD risk factor phenotypes are estimated using a variance component approach.
Subjects and method: As a first step in implementing a large, multi-center collaborative study, we recruited 381 individuals in 21 families at 8 regions across Mexico. Anthropometric and fasting blood samples were collected from all participants. We estimated the magnitude of the random effects of shared genes (heritability) using the genetic software SOLAR.
Results: We found significant heritability for phenotypes including waist circumference (0.28 [0.12]), plasma glucose (0.14 [0.08]), body mass index (BMI) (0.28 [0.10]), systolic blood pressure (BP) (0.13 [0.06]), serum cholesterol (0.31 [0.13]) and serum triglyceride (0.23 [0.10]).
Conclusions: These preliminary data represent the first heritability estimates for these phenotypes in Mexico. The results indicate that this study design offers excellent power for gene discovery relative to metabolic disease.