FTO genotype and weight gain in obese and normal weight adults from a norwegian population based cohort (the HUNT study)

Abstract

The fat mass and obesity associated gene (FTO) is associated with bodyweight and obesity. The aim of this study was to investigate ifFTO genotype affects weight gain in adulthood. We investigated the weight development over a period of 11 years in a case-control study, consisting of 1632 cases (BMI≥35kg/m2) and 3379 normal weight controls (BMI 20-24.9kg/m2) from a Norwegian population based cohort, the HUNT study. Subjects were aged 20-80 at baseline, 25% men and 75% women.FTO genotype was assessed by genotyping of the SNP rs1421085. A strong association betweenFTO and obesity was found, consistent with an additive gene effect. Cases had an average weight gain of 11.1kg, whereas controls had an average weight gain of 1.4kg. Genotype was neither associated with weight gain in obese, nor controls. Cases had an average weight gain of 10.7kg for individuals with zero risk alleles, 11.3 for one risk allele and 11.1kg for two risk alleles. Controls had an average weight gain of 1.4kg, 1.4 and 1.3 for the respective genotypes. In conclusion,FTO was associated with obesity, but not with weight gain in adults during 11 years of follow-up. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart - New York.