FTO genetic variants, dietary intake and body mass index: insights from 177,330 individuals.
Qi Q., Kilpeläinen TO., Downer MK., Tanaka T., Smith CE., Sluijs I., Sonestedt E., Chu AY., Renström F., Lin X., Ängquist LH., Huang J., Liu Z., Li Y., Asif Ali M., Xu M., Ahluwalia TS., Boer JM., Chen P., Daimon M., Eriksson J., Perola M., Friedlander Y., Gao YT., Heppe DH., Holloway JW., Houston DK., Kanoni S., Kim YM., Laaksonen MA., Jääskeläinen T., Lee NR., Lehtimäki T., Lemaitre RN., Lu W., Luben RN., Manichaikul A., Männistö S., Marques-Vidal P., Monda KL., Ngwa JS., Perusse L., van Rooij FJ., Xiang YB., Wen W., Wojczynski MK., Zhu J., Borecki IB., Bouchard C., Cai Q., Cooper C., Dedoussis GV., Deloukas P., Ferrucci L., Forouhi NG., Hansen T., Christiansen L., Hofman A., Johansson I., Jørgensen T., Karasawa S., Khaw KT., Kim MK., Kristiansson K., Li H., Lin X., Liu Y., Lohman KK., Long J., Mikkilä V., Mozaffarian D., North K., Pedersen O., Raitakari O., Rissanen H., Tuomilehto J., van der Schouw YT., Uitterlinden AG., Zillikens MC., Franco OH., Shyong Tai E., Ou Shu X., Siscovick DS., Toft U., Verschuren WM., Vollenweider P., Wareham NJ., Witteman JC., Zheng W., Ridker PM., Kang JH., Liang L., Jensen MK., Curhan GC., Pasquale LR., Hunter DJ., Mohlke KL., Uusitupa M., Cupples LA., Rankinen T., Orho-Melander M., Wang T., Chasman DI., Franks PW., Sørensen TI., Hu FB., Loos RJ., Nettleton JA., Qi L.
FTO is the strongest known genetic susceptibility locus for obesity. Experimental studies in animals suggest the potential roles of FTO in regulating food intake. The interactive relation among FTO variants, dietary intake and body mass index (BMI) is complex and results from previous often small-scale studies in humans are highly inconsistent. We performed large-scale analyses based on data from 177,330 adults (154 439 Whites, 5776 African Americans and 17 115 Asians) from 40 studies to examine: (i) the association between the FTO-rs9939609 variant (or a proxy single-nucleotide polymorphism) and total energy and macronutrient intake and (ii) the interaction between the FTO variant and dietary intake on BMI. The minor allele (A-allele) of the FTO-rs9939609 variant was associated with higher BMI in Whites (effect per allele = 0.34 [0.31, 0.37] kg/m(2), P = 1.9 × 10(-105)), and all participants (0.30 [0.30, 0.35] kg/m(2), P = 3.6 × 10(-107)). The BMI-increasing allele of the FTO variant showed a significant association with higher dietary protein intake (effect per allele = 0.08 [0.06, 0.10] %, P = 2.4 × 10(-16)), and relative weak associations with lower total energy intake (-6.4 [-10.1, -2.6] kcal/day, P = 0.001) and lower dietary carbohydrate intake (-0.07 [-0.11, -0.02] %, P = 0.004). The associations with protein (P = 7.5 × 10(-9)) and total energy (P = 0.002) were attenuated but remained significant after adjustment for BMI. We did not find significant interactions between the FTO variant and dietary intake of total energy, protein, carbohydrate or fat on BMI. Our findings suggest a positive association between the BMI-increasing allele of FTO variant and higher dietary protein intake and offer insight into potential link between FTO, dietary protein intake and adiposity.