Association of microtubule associated protein tau/Saitohin (MAPT/STH) MAPT_238bp/STH Q7R polymorphisms and Parkinson's disease: A meta-analysis.

Background: The association between the extended tau haplotype (H1) and susceptibility to Parkinson's disease (PD) was controversial in previous studies. Therefore, we performed this meta-analysis to determine whether the additional polymorphisms in MAPT_238bp and STH Q7R which both included in H1 are associated with PD.

Methods: 19 studies were identified by a search of PubMed, PDGENE, Elsevier, Springer Link, CBM (Chinese Biomedical Database), CNKI (Chinese National Knowledge Infrastructure), VIP (Chinese), and Wanfang (Chinese) databases, up to May 2014. Additionally, manual retrieval of the references of identified articles was performed. Odds ratios (ORs) with 95% confidence interval (CI) were calculated using random effects model or fixed effects model based on the between-study heterogeneity. The subgroup analyses were performed by the ethnicity. All the statistical tests were conducted using Stata 9.0.

Results: Both of MAPT_238bp/STH Q7R polymorphisms had a significant association with PD risk in all genetic models. Subgroup analyses by ethnicity showed that the association between MAPT_238bp polymorphism and PD existed in Caucasian populations.

Conclusions: The results of this meta-analysis suggested that MAPT_238bp/STH Q7R polymorphisms might modulate the risk of PD susceptibility. Certainly, additional well-designed studies are required to confirm these findings.