Meta-analysis of the association between CR1 polymorphisms and risk of late-onset Alzheimer's disease

• CR1 rs6656401 and CR1 rs3818361 polymorphisms were significantly associated with LOAD risk.
• Significantly increased risks were also observed among Asians and Caucasians.
• Significantly increased risks were also observed between HB and PB samples.

CR1 polymorphisms have been reported to be associated with late-onset Alzheimer's disease (LOAD) susceptibility. The findings of these studies, however, have been inconsistent. Therefore, we performed a meta-analysis to assess the association between CR1 variants and LOAD susceptibility. We retrieved all relevant studies of the associations between CR1 polymorphisms and the susceptibility to LOAD for the period up to March 30, 2014. The strength of the association between CR1 polymorphisms and LOAD risk was estimated by odds ratios (ORs) and their 95% confidence intervals (CIs). A total of 6 articles were eventually identified with 2752 LOAD cases and 2313 controls for the rs6656401 polymorphism, and 4 studies containing 2547 LOAD cases and 2338 controls were included for the rs3818361 polymorphism. Overall, the pooled data showed that the CR1 rs6656401 polymorphism was significantly associated with LOAD risk in the overall population (A vs. G: OR = 1.32, 95%CI = 1.17–1.50, P = 0.000; AG + AA vs. GG: OR = 1.39, 95%CI = 1.20–1.61, P = 0.000). With respect to the CR1 rs3818361 polymorphism, a statistically significant increased LOAD risk was observed in the overall population (T vs. C: OR = 1.24, 95% CI = 1.13–1.37, P = 0.000; TT + TC vs. CC: OR = 1.30, 95% CI = 1.15–1.46, P = 0.000; TT vs. TC + CC: OR = 1.35, 95% CI = 1.06–1.71, P = 0.014). This meta-analysis demonstrated significant associations of both the CR1 rs6656401 and CR1 rs3818361 polymorphisms with LOAD susceptibility.