The influence of polymorphisms of fat mass and obesity (FTO, rs9939609) and vitamin D receptor (VDR, BsmI, TaqI, ApaI, FokI) genes on weight loss by diet and exercise interventions in non-diabetic overweight/obese Asian Indians in North India

Objective The aim of the present study was to evaluate polymorphisms of fat mass and obesity (FTO; rs9939609) and vitamin D receptor (VDR, FokI (rs2228570), BsmI (rs1544410), ApaI (rs7975232), and TaqI (rs731236)] genes on weight loss after lifestyle interventions in Asian Indians. Methods In this 6-month pre-post intervention trial, 110 overweight/obese men and women underwent diet and exercise interventions for 180 days resulting in reduction in body weight, (5.1 kg, p < 0.001), waist circumference, and skinfolds. Results Association of the following genotypes was seen in those with >= 5% weight loss: TT of FTO polymorphism; 35 (81.4%) [OR (95% CI) AT, 2.5 (0.6, 10.9); TT, 6.9 (1.6, 28.2); with reference to AA], tt of VDRTaqII polymorphism, 12 (92.3%) [OR (95% CI); tt, 32.2 (2.4, 436.4); TT, 0.5 (0.08, 3.1); all with reference to Tt], bb of VDRBsmI polymorphism; 27 (65.8%) [OR (95% CI) Bb, 0.2 (0.04, 0.9); bb, 10.6 (0.9, 120.3); all with reference to BB] after adjusting for other genotypes. Further, analysis of combined influence of genotypes conferring maximum weight loss showed that the following had high odds of >= 5% weight loss: (1) TT of FTO gene in combination with BB/Bb of VDRBsmI and TT/Tt of VDRTaqI [OR (95% CI) 5.1 (1.5, 17.4)], (2) bb of BsmI and AA/AT of FTO and tt of TaqI [OR (95% CI) 3.2 (0.3, 31.7)], and (3) bb of BsmI plus TT of FTO and tt of TaqI. Conclusions The above observations suggest a significant and independent role of the genotypes of FTO and VDR in influencing weight loss after lifestyle intervention in Asian Indians.