Age; sex; race; center; BMI; waist circumference; serum magnesium, calcium, and creatinine levels; physical activity levels; parental history of DM; presence of hypertension; systolic blood pressure; FBG and fasting insulin levels; income; and use of beta blockers, diuretics, ACEI. +dietary magnesium intake, dietary calcium intake (for dietary K+). The gene discussed is INS; the disease is diabetes mellitus.