Proline dehydrogenase gene (PRODH) polymorphisms and schizophrenia susceptibility: a meta-analysis

Previous studies have been conducted to explore the association between proline dehydrogenase gene (PRODH) polymorphisms and schizophrenia (SZ) susceptibility, but providing the controversial results. Here we performed this meta-analysis to determine whether PRODH variants were associated with SZ risk. Relevant studies were screened by retrieving online database PubMed, Web of Science, Embase, China National Knowledge Infrastructure (CNKI) and SZGene from inception to December 2016. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated based on genotype data or allele frequency to evaluate the strength of this association. For rs372055, eleven studies with 3398 SZ patients and 3171 controls were included and the results indicated that people carrying the T allele was not associated with SZ risk in allele frequency model (C vs T, OR = 1.12, 95%CI = 0.96-1.32). However, results from subgroup analysis showed a significant relationship between rs372055 and SZ risk in dominant genetic model (CC + CT vs TT, OR = 1.26, 95% CI = 1.05-1.50) and heterogeneous model (CT vs TT, OR = 1.26, 95% CI = 1.05-1.52) in Asian, but not in Caucasian. For polymorphisms rs383964, rs450046, rs385440 and rs2870983, no associations were found between these polymorphisms and SZ susceptibility in allele frequency. This meta-analysis suggests that rs372055 (C/T) polymorphism in PRODH gene is associated with increased SZ risk only in Asian.