Methods: For population genetic purposes, DNA samples from 239 patients with sporadic PD and 84 healthy controls were included and genotyped for IL-10_rs1800896, IL-10_rs1800872, IL-13_rs20541, IL-17A_rs2275913, and IL-17_rs8193036 variants by allelic discrimination in real-time PCR. Here, IL17A is linked to Parkinson disease.