FTO genotype is associated with body mass index and waist circumference in Mexican young adults

Individual variations in the fat mass and obesityassociated (FTO) gene have been associated with obesity and BMI in diverse populations, but there are no reports in young Mexicans. We explored the association of a common FTO single-nucleotide polymorphism (SNP, rs805704) with obesity-related phenotypes in Mexican young adults. The FTO-SNP was genotyped using the fluorescent polarization method in college-age, apparently healthy subjects from the “UP AMIGOS” cohort (n = 251, 18 25 yrs). Homozygotes for the A allele (15%, n = 38) were heavier (1.6 kg/m and 6.2 kg) and had a larger waist circumference (WC, 4.8 cm) than G allele carriers. The FTO genotype was associated with BMI, weight and WC independently of age and sex and explained 2.7 to 3.1% of the variance in obesity-related phenotypes. The FTO genotype was also associated with fasting glucose (P = 0.0283). No other associations were found in the additive model. Despite our small sample size, we found that the FTO-rs805704 genotype influences obesity-related phenotypes young Mexicans. Previously observed FTO associations with fasting glucose were replicated. Previously reported associations with other metabolic traits likely represent the long-term consequences of obesity.