Influence of FTO (Fat mass and obesity) gene and parental obesity on Brazilian children and adolescents adiposity.

Objectives Evaluate the influence of the genetic variant rs9939609 of the FTO gene on anthropometric characteristics and whether parental obesity is related to children and adolescents being overweight. Methods A total of 2,364 children and adolescents between 6 and 17 years old were genotyped and the lipid profile, plasma glucose level, and anthropometric characteristics were measured to assess adiposity. Results The AA genotype (risk) was associated with higher body mass index (BMI Z-score; p = 0.006), waist circumference (WC; p = 0.001), and triglycerides (p = 0.033). The association of the participants' adiposity characteristics with the parents' BMI and FTO genotypes showed an association of the BMI Z-score when either the mother or father was overweight or obese (p = 0.028 and p = 0.029). In the overweight or obese father/eutrophic mother, we also observe an association of FTO rs9939609 with WC (p = 0.039). The effect of these variables on the risk of obesity was also tested: overweight or obese mother (OR = 1.82, p = 0.041), overweight and obese parents (OR = 3.09, p < 0.0001), and FTO rs9939609 AA genotype (OR = 2.08, p = 0.0004) were associated. With regard to altered WC and high body fat percentage (BF%), either overweight or obese parents (OR = 2.39, p < 0.0001; OR = 1.92, p < 0.002) showed an association. The FTO rs9939609 AA genotype (OR = 1.99, p = 0.0002) was associated with altered WC. Conclusions The results show that parental weight also contributes to obesity and may interact with the FTO genetic make-up.