Association of Choline Acetyltransferase Gene Polymorphisms (SNPs rs868750G/A, rs1880676G/A, rs2177369G/A and rs3810950G/A) with Alzheimer’s Disease Risk: A Meta-Analysis

BACKGROUND Epidemiological studies have investigated the role of choline acetyltransferase (ChAT) in Alzheimer's disease (AD). ChAT gene polymorphisms (SNPs rs868750G/A, rs1880676G/A, rs2177369G/A, and rs3810950G/A) may be associated with the risk of AD. In this meta-analysis, we determined the relationship between the four polymorphisms and the risk of AD. METHODS We searched MEDLINE, EMBASE, and HuGEnet databases for studies linking the four polymorphisms with AD risk. We included 16 articles in our meta-analysis to assess the association between the four polymorphisms and susceptibility to AD by calculating the pooled odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS The combined results showed no significant association with rs1880676G/A and rs2177369G/A polymorphisms. The risk of AD (GG+GA versus AA: OR = 0.01, 95%CI = 0.01-0.02, P < 0.05; GG versus GA+AA: OR = 0.85, 95%CI = 0.72-1.00, P = 0.05; GA versus AA: OR = 0.60, 95% CI = 0.37-0.98, P = 0.04) with rs868750G/A polymorphism, or the association of rs3810950G/A polymorphism with AD risk in the overall population (GA versus AA: OR = 0.64, 95% CI = 0.44-0.93, P = 0.02; GG+GA versus AA: OR = 0.62, 95% CI = 0.39-0.97, P = 0.04) or Asian group (GA versus AA: OR = 0.50, 95% CI = 0.32-0.76, P = 0.001, and GG+GA versus AA: OR = 0.46, 95% CI = 0.30-0.09, P = 0.0002) was demonstrated. CONCLUSIONS Our meta-analysis suggested that rs1880670G/A, and rs2177369 G/A polymorphisms were not risk factors for AD. However, rs3810950G/A, or rs868750G/A genetic polymorphism was a genetic risk factor for the development of AD. The rs3810950G/A polymorphism had a negative effect on the risk of AD for GA or GG+GA genotypes compared with AA in the overall population or Asians.