Genetic associations of CLU rs9331888 polymorphism with Alzheimer's disease: A meta-analysis

Recent studies showed the Clusterin gene (CLU) is associated with Alzheimer's disease (AD). However, studies investigating the association of CLU single-nucleotide polymorphism (SNP) rs9331888 with AD are controversial. We then performed a meta-analysis to assess the association between CLU SNP rs9331888 and AD. Computerized bibliographic searches of PUBMED and AlzGene database were conducted for the period up to July, 2014. The strength of the association between SNP rs9331888 and AD was estimated by odds ratios (ORs) and OR 95% confidence intervals (CIs). A total of 11 studies composed of 8766 AD cases and 11,366 controls were included in this study. Significant association of SNP rs9331888 with AD was found in Caucasian population among allelic model (C vs. G: OR = 1.12, 95%CI = 1.06-1.17, P < 0.001), additive model (CC vs. GG: OR = 1.25, 95%CI = 1.12-1.40, P < 0.001), recessive model (CC vs. CG + GG: OR = 1.20, 95%CI = 1.07-1.34, P = 0.001), and dominant model (CC + CG vs. GG: OR = 1.13, 95%CI = 1.06-1.21, P < 0.001). No significant association among these models was found in Asian and overall populations. Sensitivity analysis found that one study caused the distinct heterogeneity in Asian subgroup. Our analysis demonstrated that CLU SNP rs9331888 might be associated with an increased AD risk in Caucasian population, but not in Asian population.