National Institute for Nutrition and Food Safety, Chinese Center for Disease Control and Prevention, Beijing, China.
BMC Med Genet. 2010 Sep 22;11:136. doi: 10.1186/1471-2350-11-136.
Fat-mass and obesity-associated (FTO) gene is a gene located in chromosome region 16q12.2. Genetic variants in FTO are associated with the obesity phenotype in European and Hispanic populations. However, this association still remains controversial in Asian population. We aimed to test the association of FTO genetic variants with obesity and obesity-related metabolic traits among children living in Beijing, China.
We genotyped FTO variants rs9939609 in 670 children (332 girls and 338 boys) aged 8-11 years living in Beijing, and analyzed its association with obesity and obesity-related metabolic traits. Overweight and obesity were defined by age- and sex-specific BMI reference for Chinese children. Obesity-related metabolic traits included fasting plasma glucose, lipid profiles, leptin, ghrelin, adiponectin and blood pressures.
The frequency of rs9939609 A allele was 12.2%, which was 21.9% for the heterozygote and 1.2% for the homozygote of the A allele. The obesity prevalence among the carriers of AA/AT genotypes was significantly higher than that among those with TT genotype (36.4% vs. 22.6%, P=0.004). Compared to the carrier of TT genotype, the likelihood of obesity was 1.79 (95% confidence interval (95% CI) 1.20-2.67, P=0.004) for the carrier of AA/AT genotype, after adjustment of sex, age and puberty stages. The BMI Z-score of children with AA/AT genotype were significantly higher than that of their counterparts with the TT genotype (1.1±0.1 vs. 0.8±0.1, P=0.02). The concentration of triglyceride was 1.03±0.52 mmol/L among TT carrier and 1.13±0.68 mmol/L among AA/AT carrier (P=0.045). While, the concentrations of adiponectin were 18.0±0.4 μg/ml among carriers of TT and 16.2±0.7 μg/ml among subjects with AA/AT genotype (P=0.03). The level of glucose marginally increased in the AA/AT genotype subjects (4.67±0.40 mmol/L vs. 4.60±0.35 mmol/L, P=0.08). The evidence of association was reduced after adjustment for BMI (P=0.38 for triglyceride, P=0.20 for adiponectin and glucose). There was weak evidence of association between rs9939609 and other obesity-related metabolic traits including total cholesterol (3.92±0.03 mmol/L vs. 4.02±0.05 mmol/L, P=0.10), insulin (2.69±1.77 ng/ml vs. 3.12±2.91 ng/ml, P=0.14), and insulin resistance (HOMA-IR 0.56±0.03 vs. 0.66±0.05, P=0.10).
Genetic variation in the FTO gene associates with obesity in Chinese children.
脂肪质量和肥胖相关（FTO）基因是位于染色体 16q12.2 区域的一个基因。FTO 基因中的遗传变异与欧洲和西班牙裔人群的肥胖表型有关。然而，这种关联在亚洲人群中仍然存在争议。我们旨在检验 FTO 基因变异与中国北京儿童肥胖和肥胖相关代谢特征的关系。
我们对 670 名 8-11 岁的北京儿童（332 名女孩和 338 名男孩）进行了 FTO 变体 rs9939609 的基因分型，并分析了其与肥胖和肥胖相关代谢特征的关系。超重和肥胖通过中国儿童年龄和性别特异性 BMI 参考值来定义。肥胖相关代谢特征包括空腹血糖、血脂谱、瘦素、生长激素释放肽、脂联素和血压。
rs9939609A 等位基因的频率为 12.2%，杂合子为 21.9%，纯合子为 1.2%。AA/AT 基因型携带者的肥胖患病率明显高于 TT 基因型携带者（36.4% vs. 22.6%，P=0.004）。与 TT 基因型携带者相比，AA/AT 基因型携带者肥胖的可能性为 1.79（95%置信区间 95%CI 为 1.20-2.67，P=0.004），调整性别、年龄和青春期阶段后。AA/AT 基因型携带者的 BMI Z 评分明显高于 TT 基因型携带者（1.1±0.1 vs. 0.8±0.1，P=0.02）。TT 携带者的甘油三酯浓度为 1.03±0.52mmol/L，而 AA/AT 携带者的甘油三酯浓度为 1.13±0.68mmol/L（P=0.045）。然而，TT 携带者的脂联素浓度为 18.0±0.4μg/ml，而 AA/AT 基因型携带者的脂联素浓度为 16.2±0.7μg/ml（P=0.03）。AA/AT 基因型携带者的血糖水平略有升高（4.67±0.40mmol/L vs. 4.60±0.35mmol/L，P=0.08）。调整 BMI 后，关联的证据减少（甘油三酯 P=0.38，脂联素和葡萄糖 P=0.20）。rs9939609 与其他肥胖相关的代谢特征之间存在弱关联，包括总胆固醇（3.92±0.03mmol/L vs. 4.02±0.05mmol/L，P=0.10）、胰岛素（2.69±1.77ng/ml vs. 3.12±2.91ng/ml，P=0.14）和胰岛素抵抗（HOMA-IR 0.56±0.03 vs. 0.66±0.05，P=0.10）。
FTO 基因的遗传变异与中国儿童肥胖有关。
