A Cross-Sectional Study Investigating the Relationship Between the FTO Gene Polymorphism in Relation to Obesity...

Obesity affects 18%-25% of adolescents globally and represents a major public health challenge. Genetic factors contribute to obesity susceptibility, with the FTO gene variant rs9939609 consistently associated with obesity in adults; however, evidence in adolescents is limited. This study examined the association between FTO and obesity traits in adolescents and explored potential interactions with vitamin D status.

In this cross-sectional study, 509 adolescents aged 10-15 years were genotyped for FTO rs9939609. Obesity traits, including BMI, BMI z-score, and waist circumference, were assessed. Associations with genotype were analyzed using an additive genetic model, and potential interactions with vitamin D status were evaluated.

The A allele was significantly associated with higher adiposity: BMI (β = 1.29 kg/m², p = 0.0008) and waist circumference (β = 3.24 cm, p = 0.001). Each additional risk allele increased the odds of having overweight or obesity by 53% (OR = 1.53, 95% CI: 1.19-1.98, p = 0.001). No significant interaction was observed between FTO and vitamin D status (p > 0.05).

This first report from the Arabian Gulf region confirms the association between FTO rs9939609 and adiposity in adolescents, underscoring the contribution of genetic factors to obesity risk in young populations.