Effect of obesity gene variant influenced by age

(HealthDay)—A genetic variant associated with obesity risk (FTO) has a greater effect on body mass index (BMI) in young adults than older adults, according to a study published online Jan. 8 in Diabetes.

Mariaelisa Graff, Ph.D., from the University of North Carolina at Chapel Hill, and colleagues analyzed the associations of five established obesity risk variants with BMI in 34,053 European Americans (18 to 100 years old) across four periods of adulthood, and by menopausal status in women and stratification by 50 years of age in men.

The researchers found that the association of the FTO (rs8050136) variant with BMI was heterogeneous across all four age ranges, with the largest effect observed in young adults (18 to 25 years old). This did not appear to be specifically related to menopausal status in women or the cut-off of 50 years of age in men. There was no observed heterogeneity in the association of the GNPDA2, MTCH2, TMEM18, and NEGR1 variants with BMI.

"Genetic predisposition to obesity may have greater effects on body weight in young compared with older adulthood for FTO, suggesting changes by age, generation, or secular trends," Graff and colleagues write.