SNCA rs356219 variant increases risk of sporadic Parkinson's disease in ethnic Chinese.

Alpha-synuclein gene (SNCA) polymorphisms have been associated with Parkinson's disease (PD). A recently published genome-wide association study (GWAS) meta-analysis from the USA and Europe found a strong association between SNCA rs356219 and PD. Considering the population-specific heterogeneity, we investigated the role of SNCA rs356219 as PD susceptibility in a large Han Chinese population of 685 patients and 569 controls. The SNCA rs356219-G allele was found to increase the risk to develop PD (OR = 1.81, 95% CI: 1.54-2.13, P = 5.71E-13). The meta-analysis revealed that the frequency of AG + GG genotypes higher in PD than in control subjects (OR = 1.85, 95% CI: 1.56-2.19, P = 0.00001) in the Asian population. PD patients with AG + GG genotypes were associated with earlier age at onset compared with those with AA genotype. No such significant association was observed in the clinical presentation for gender, age at onset, and onset symptoms. Our study provides strong support for the susceptibility role of SNCA rs356219 in sporadic PD in a Han Chinese population from mainland China and the meta-analysis also revealed a similar finding in the Asian population.