Common variation in the fat mass and obesity-associated (FTO) gene confers risk of obesity and modulates BMI in the Chinese population.
OBJECTIVE
Genetic variants in the fat mass and obesity-associated (FTO) gene have been linked with obesity and type 2 diabetes in European populations. We aimed to test the role of FTO genetic variants in obesity and type 2 diabetes in the Chinese population.


METHODS
We genotyped 19 single-nucleotide polymorphisms (SNPs) spanning from the 3' end of the neighboring RPGRIP1L gene to the 5' flanking region of the FTO gene. We analyzed their associations with obesity (638 case and 1,610 control subjects), type 2 diabetes (759 case and 784 control subjects), and obesity-related traits in nondiabetic subjects.


RESULTS
Among the 19 SNPs, the rs9939609 A allele was strongly associated with obesity (P = 7.0 x 10(-4)) and BMI (P = 0.0024) in the Chinese population. The odds ratio for obesity was 2.60 (95% CI 1.24-5.46) (P = 0.011) for the AA genotype and 1.32 (1.05-1.66) (P = 0.018) for the AT genotype compared with the TT genotype. Each additional copy of the rs9936609 A allele was associated with a BMI increase of approximately 0.37 kg/m(2). The rs9939609 A allele was substantially less common in the Chinese population than in the European population (12.6 vs. 45%). We did not find significant associations of the 19 SNPs with type 2 diabetes or other obesity-related traits.


CONCLUSIONS
Genetic variation in the FTO gene is strongly associated with obesity and BMI in the Chinese population. The risk variant is less common in the Chinese population, but its effect size on BMI is comparable with that in the European population.
Chang
Yi-Cheng
YC
Department of Internal Medicine, National Taiwan University Hospital Yunlin Branch, Yunlin, Taiwan.
Liu
Pi-Hua
PH
Lee
Wei-Jei
WJ
Chang
Tien-Jyun
TJ
Jiang
Yi-Der
YD
Li
Hung-Yuan
HY
Kuo
Shan-Shan
SS
Lee
Kuang-Chin
KC
Chuang
Lee-Ming
LM
D000328:Adult; D000071516:Alpha-Ketoglutarate-Dependent Dioxygenase FTO; D044466:Asian People / Q000235:genetics*; D015992:Body Mass Index; D002681:China; D003598:Cytoskeletal Proteins; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000208:ethnology / Q000235:genetics* / Q000503:physiopathology; D020641:Polymorphism, Single Nucleotide; D011506:Proteins / Q000235:genetics* / Q000502:physiology; D012307:Risk Factors
D003598:Cytoskeletal Proteins; D011506:Proteins; C415903:RPGRIP1 protein, human; D000071516:Alpha-Ketoglutarate-Dependent Dioxygenase FTO; C526492:FTO protein, human