Introduction: The purpose of this study was to examine whether the insertion (I) and deletion (D) polymorphism of the angiotensin-converting enzyme (ACE) confers susceptibility to schizophrenia and Parkinson's disease (PD).
Materials and methods: A meta-analysis was performed of the associations between the ACE I/D polymorphism and schizophrenia and PD.
Results: Thirteen studies with 2024 cases and 2230 controls comprising eight studies on schizophrenia and five on PD were included in the meta-analysis. The meta-analysis revealed no association between the ACE D allele and schizophrenia (OR = 0.990, 95% CI = 0.889-1.102, p = 0.856) or PD (OR = 1.067, 95% CI = 0.907-1.255, p = 0.433). Stratification by ethnicity indicated no association between the ACE D allele and schizophrenia in European, Asian, or Turkish ethnic groups (OR = 0.896, 95% CI = 0.566-1.419, p = 0.640; OR = 1.057, 95% CI = 0.903-1.238, p = 0.492; OR = 1.111, 95% CI = 0.889-1.389, p = 0.354, respectively). Ethnicity-specific meta-analysis was not conducted for PD because only one ethnic PD study was available.
Conclusions: This meta-analysis found no association between the ACE I/D polymorphism and schizophrenia or PD.
Keywords: Angiotensin-converting enzyme; Parkinson’s disease; meta-analysis; polymorphism; schizophrenia.
© The Author(s) 2014.