A meta-analysis of leucine-rich repeat kinase 2 (LRRK2) polymorphisms in Alzheimer's disease.

Pathogenesis and the development of Alzheimer's disease (AD) are subject to several environmental and genetic factors. This study was aimed to estimate the frequency of mutations in leucine-rich repeat kinase 2 (LRRK2) gene to examine the association between these mutations and risk of AD. For finding the articles, four databases including PubMed, Web of Science, Scopus, and Cochrane Library were checked up to August 2018. An analysis was done by RevMan 5.3 using crude odds ratio (OR) and 95% confidence intervals (CIs) to determine the association between LRRK2 polymorphisms and the risk of AD. Of 359 articles identified in the databases, 13 studies were included and analysed in the meta-analysis. There was no significant risk of AD related to five LRRK2 polymorphisms (rs33949390, rs34778348, rs7308720, rs34637584, and rs35870237). The results showed that LRRK2 variants (p.R1628P, p.G2385R, p.N551K, p.G2019S, and p.I2020T) were not associated with the risk of AD and were not a common cause of AD in populations. Nevertheless, p.R1628P can be examined in patients with AD in other populations in the future studies.