Meta-analysis of the influence of Parkin p.Asp394Asn variant on the susceptibility of Parkinson's disease.

Parkinson's disease (PD) is one of the most common neurodegenerative disorders. The Parkin p.Asp394Asn variant (c.1281G>A) has been investigated as a potential genetic hallmark of PD, but studies investigating the association between the variant and PD have reported conflicting results. Therefore, we conducted this meta-analysis to assess whether pooled results show the association. We performed structured literature searches in MEDLINE, EMBASE, Cochrane Library, and China Academic Journals databases for studies addressing the association between Parkin p.Asp394Asn variant and PD. The meta-analysis was conducted in five genetic models: additive, dominant, recessive, heterozygous, and homozygous, with the odds ratio (OR) as the measure of association. When all 7 studies involving 2425 subjects (1213 cases and 1212 controls) were pooled into the analysis, there was no evidence for significant association between Parkin p. Asp394Asn variant and PD risk in additive genetic model (OR=1.06, 95% confidence interval (CI)=0.66-1.70, P=0.825). The OR for the dominant model was 1.07 (95% CI=0.69-1.67) while the OR for the recessive model was 0.84 (95% CI=0.16-4.35). The OR for the heterozygote was 1.08 (95% CI=0.73-1.60) while the OR for the homozygote was 0.85 (95% CI=0.16-4.61). Concluding, our study does not support an association between the Parkin p.Asp394Asn variant and PD risk.