Influence of physical activity on the association between the FTO variant rs9939609 and adiposity in young adults

Muc, Magdalena; Padez, Cristina and Manco, Lic\'\inio (2015). Influence of physical activity on the association between the FTO variant rs9939609 and adiposity in young adults. American Journal of Human Biology, 27(5) pp. 734–738.

DOI: https://doi.org/10.1002/ajhb.22712

Abstract

Objectives To investigate in a population sample of Portuguese young adults the association of the FTO variant rs9939609 with obesity, BMI, and body-fat and interaction with physical activity (PA) on obesity-susceptibility.

Methods SNP rs9939609 A/T was genotyped in 550 subjects (231 males and 319 females; 18–36 years old; mean age 21 years old) by TaqMan assay. PA was assessed with a validated self-reported questionnaire of IPAQ.

Results We replicated the association of rs9939609-A risk allele with BMI (P = 0.04) and fat-mass (P = 0.031), and with overweight (including obesity) under a recessive model (P = 0.034). Stratified analyses showed (i) a significant association with overweight/obesity in inactive individuals (P = 0.02) but not in a group reporting participation in sports (P = 0.97). Spearman's correlation test suggested that the impact of a successive increase in PA was a decrease in the body-fat percentage (r = −0.16; P = 0.0002), which is accentuated for homozygous AA (r = −0.34; P = 0.002), and an increase in BMI (r = 0.14; P = 0.001), with a statistically significant correlation for homozygous TT (r = 0.22; P = 0.002).

Conclusions This study reveals interactions between rs9939609 and PA on obesity indices in Portuguese young adults, suggesting a change in the different body components (lean and fat mass) depending on the FTO genotypes.