LOC387715/HTRA1 gene polymorphisms and susceptibility to age-related macular degeneration: A HuGE review and meta-analysis

PURPOSE To examine the association of age-related macular degeneration (AMD) with HtrA serine peptidase 1 (HTRA1) gene rs11200638 G→A polymorphism and LOC387715/ ARMS2 gene rs10490924 G→T polymorphisms, and to evaluate the magnitude of the gene effect and the possible genetic mode of action. METHODS We searched the US National Library of Medicine's PubMed, Embase, OMIM, ISI Web of Science, and CNKI databases in a systematic manner to retrieve all genetic association studies on the HTRA1 (rs11200638) and LOC387715/ ARMS2 (rs10490924) gene polymorphisms and AMD. We performed a meta-analysis conducted with Stata software, version 9.0. RESULTS Individuals who carried the AA and AG genotypes of HTRA1 gene rs11200638 G→A polymorphism had 2.243 and 8.669 times the risk of developing AMD, respectively, when compared with those who carry the GG genotype. Individuals carrying the TT and TG genotypes of LOC387715/ ARMS2 gene rs10490924 G→T polymorphism had 7.512 and 2.353 times the risk of developing AMD, respectively, compared with those who carry GG genotype. These results suggested a "moderate" codominant, multiplicative genetic mode; that is, both HTRA1 rs11200638 G→A polymorphism and LOC387715/ARMS2 rs10490924 G→T polymorphism play important roles in the pathogenesis of AMD. We found no evidence of publication bias. Between-study heterogeneity was found in both allele-based analysis and genotype-based analysis. CONCLUSIONS HTRA1 rs11200638 G→A polymorphism and LOC387715/ARMS2 rs10490924 G→T polymorphism play important roles in AMD. Gene-gene and gene-environmental interactions, as well as precise mechanisms underlying common variants in the HTRA1 gene and LOC387715/ ARMS2 gene, potentially increase the risk of AMD and need further exploration.