Background: To date, many studies have examined the correlation between Monoamine oxidase B (MAOB) intron 13 A/G polymorphisms and the susceptibility to Parkinson's disease (PD). However, the results of these studies are inconclusive.
Methods: In order to confirm this correlation, a meta-analysis of 15 studies was performed and the dichotomous data are presented as odds ratios (ORs) and 95% confidence intervals (CIs).
Results: Carriers of the MAOB intron 13 A allele were more likely to have PD than carriers of the G allele in the Asian population (OR = 1.182, 95% CI = 1.012-1.380, p < 0.05). When combined with the COMT LL genotype, the MAOB intron 13 AA/(A) genotype increased the risk of PD susceptibility more than with the GA genotype or GG + GA/(G) genotype (AA/(A) vs. GG + GA/(G): OR = 1.610, 95% CI = 1.094-2.369; AA/(A) vs. GA: OR = 1.621, 95% CI = 1.004-2.619). Irrespective of whether individuals were in the AA/(A) genotype or GG + GA/(G) genotype subgroup, this meta-analysis indicated that smoking was a PD-preventive factor (AA/(A): OR = 1.823, 95% CI = 1.150-2.891; GG + GA/(G): OR = 2.245, 95% CI = 1.277-3.948).
Conclusion: The results of this meta-analysis suggest that people with the MAOB intron 13 A allele have an increased risk of PD in the Asian population, especially when combined with the COMT LL genotype.
Keywords: MAOB gene; Parkinson's disease; meta-analysis; polymorphism.