东亚人群VD受体基因ApaI多态性与银屑病易感性的Meta-分析

目的采用Meta-分析的方法对东亚人群VDR基因ApaI多态性与银屑病易感性的关系进行综合评价。方法系统检索所有2012年1月前在PubMed、中国生物医学文献数据库（CBM）上发表的ApaI多态性与银屑病关联分析的文献,然后按一定的标准选择合格的研究并从每个纳入研究中提取相关信息。对于ApaI多态位点,我们进行基于等位基因、显性遗传模式和隐性遗传模式关联研究的Meta-分析。通过固定或随机效应模型计算合并的优势比（Odds ratio,OR）。通过敏感性分析确定异质性并探索其来源。用漏斗图和Egger检验检测出版偏倚。结果有4个研究符合我们的标准进入本Meta-分析。基于等位基因、显性及隐性遗传模式关联研究的Meta-分析结果显示：在东亚人群中,等位基因A不是银屑病发病的危险因素：异质性χ2=14.48,P=0.002,I2=79.3%;OR随机效应模型=1.110,95%CI=0.667～1.847,z=0.40,P=0.689;基因型AA与aa均与银屑病发病不相关：显性遗传模式,异质性χ2=13.76,P=0.003,I2=78.2%,OR随机效应模型=1.034,95%CI=0.547,1.955,z=0.10,P=0.918;隐性遗传模式,异质性χ2=10.61,P=0.014,I2=71.7%,OR随机效应模型=1.406,95%CI=0.514,3.848,z=0.66,P=0.507。敏感性分析显示来自韩国的一个研究是异质性的主要来源,当排除该研究后,同样表现了上述趋势。另外,本Meta-分析所纳入的文献均不存在显著的出版偏倚。结论在东亚人群中,维生素D受体基因ApaI位点不是银屑病的易感位点。

Apal polymorphism in vitamin D receptor (VDR) gene and the risk of psoriasis in East Asian populations:a meta-analysis

Objective To overcome the limitations of individual studies,a meta-analysis was conducted to assess the association between ApaI polymorphism and psoriasis susceptibility in East Asian populations.Methods All genetic association studies that investigated the association of the ApaI polymorphism with the development of psoriasis published before Jan 2012 were searched in PubMed and CBM.All retrieved papers were selected according to the inclusion criteria and the eligibility ones were entered into our meta-analysis.For each included study,the informations,such as first author,year of publication,country where the trial was conducted,sample origin,numbers of cases and controls,and distributions of allele and genotype in both case and control groups,were extracted.For ApaI polymorphism,we explored the significance of the associations for the allele contrast as well as the dominant and recessive models.The pooled odds ratio（OR） was calculated using a fixed-or a random-effects model.Heterogeneity was identified by sensitivity analysis and publication bias was examined by funnel plot and Egger＇s test.Results A total of 4 studies that met our inclusion criteria were included.For the ApaI polymorphism,allele A produced no significant result in psoriasis patients of East Asians（heterogeneity χ2=14.48,P=0.002,I2=79.3%;ORrandom-effect model =1.110,95% CI=0.667-1.847,z=0.40,P=0.689）,and also with dominant model（heterogeneity χ2=13.76,P=0.003,I2=78.2%;ORrandom-effect model=1.034,95% CI=0.547,1.955,z=0.10,P=0.918） and recessive model（heterogeneity χ2=10.61,P=0.014,I2=71.7%;ORrandom-effect model =1.406,95% CI=0.514,3.848,z=0.66,P=0.507）.To explore the heterogeneity,a sensitivity analysis was performed and the result showed that a Korean study accounted for the mentioned heterogeneity.After removing this study,the heterogeneity no longer existed and the result persisted.The funnel plot and Egger＇s test suggested the absence of publication bias in this meta-analysis.Conclusions It seems from our meta-analysis that ApaI polymorphism in VDR gene might not be a susceptibility locus of psoriasis in East Asian populations.