瘦素基因启动区-2548G／A多态性和肥胖关系的Meta分析

Association of leptin gene-2548 G /A polymorphism with obesity: a Meta-analysis

目的探讨瘦素基因(LEP)5’端非翻译区-2548位点上G/A单核苷酸多态性(SNP)与肥胖的关系。方法用Meta分析法研究LEP-2548 G/A多态性与肥胖的关系;分别采用显性和隐性模型进行分析,计算纳入研究的合并优势比(OR)估计值及其95%CI,用统计量I2判断各研究间的异质性,用Egger检验分析发表偏倚。结果经过HWE检验后,最后选择了11项研究,包括了5210名受试者(2541名肥胖者和2669名对照)。在显性模型分析中,OR=1.14(95%CI:0.98-1.31,P=0.08);在隐性模型分析中,合并OR=1.03(95%CI:0.85-1.25,P=0.76),说明LEP-2548 G/A多态性和肥胖之间没有显著联系。但是,亚组分析时发现在美洲人群中,GG纯合基因型是肥胖的一个显著性危险因子[OR=1.53(95%CI:1.17-2.00),P=0.002]。在其他地区未发现显著性结果。结论在总人群中LEP-2548G/A多态性与肥胖之间无相关性,但在美洲人群中,GG基因携带是肥胖一个显著的危险因素。

Objective To examine the association between a common single nucleotide polymorphism identified in the 5＇ untranslated region of leptin gene （LEP-2548 G/A SNP） and obesity. Methods Meta-analysis of published studies, included if subjects were genotyped at polymorphism LEP-2548 G/A and both obese and nonobese subjects were selected, based on a reported cutoff BMI limit. Meta-analysis of the total and subgroup populations was conducted using dominant and recessive models, and OR and 95% CI were calculated in the fixed-effect model. 12 statistic was calculated to examine heterogeneity, and publication bias was evaluated by Egger test. Results After testing each control group for Hardy-Weinberg equilibrium, the final selection enrolled 11 studies, including 5210 subjects （2541 obesity subjects and 2669 healthy）. In the combined analysis of all eligible studies, none significant association was identified between LEP-2548 G/A SNP and obesity either in dominant model or the recessive one with pooled odds ratios 1.14 （95% CIO. 98 - 1.31, P =0.08） and 1.03（95% CIO. 85 -1.25, P =0.76）. However, subgroup analysis found a significant association of GG homozygote in American population [0R=1.53 （95% CI 1.17-2.00）, P=0.002]. No significant evidence was found in other populations. Discussion This first meta- analysis of data from published studies did not detect any association between the polymorphism of LEP-2548 G/A and risk of obesity in overall population. Nevertheless, the presence of the GG genotype in the gene appears to be a significant risk factor for obesity in American.