Objective: To investigate the possible association of IVS5-5G>A polymorphism, positioned in the upstream region of exon 5 of PINK1 gene with the risk for sporadic late onset Parkinson disease (LOPD) in Chinese.
Methods: Intronic regulatory sequence analysis was performed using the web-based in-silico analysis. The authors performed an association study using a case-control series (comprising 382 LOPD patients and 336 controls, Chinese of Han ancestry). Genotyping was performed by PCR-based denaturing high performance liquid chromatography (DHPLC) combined with sequencing analyses. Allele and genotype frequencies were compared by the Chi-square test.
Results: In-silico analysis showed that the intronic IVS5-5G>A polymorphism was located within acceptor site of exon 5 and may be the functional single polymorphism (SNP) in the regulatory region with impact on the splicing of PINK1 gene. Those result yielded statistical significant evidence for the association of PINK1 IVS5-5G>A polymorphism with risk for typical PD in Chinese Han population (OR=1.95, 95%CI: 1.29-2.94, P=0.0012). Homozygote of A allele may have increased risk for LOPD (OR=2.45, 95%CI: 1.27-4.72, P=0.009).
Conclusion: The authors provide the first evidence that the common genetic variation PINK1 IVS5-5G>A may contribute to the risk of LOPD in Chinese population.