Interleukin-10 (IL10) and tumor necrosis factor α (TNF) gene polymorphisms in Parkinson's disease patients

Recent studies revealed that inflammatory processes might play an important role in the pathogenesis of Parkinson's disease (PD). We hypothesized that genetically determined differences in the immune response, especially in anti- and pro-inflammatory cytokines production might influence the risk for the development and/or onset of sporadic PD. In the present study, we investigated the genetic polymorphisms of the 100 (-1082 and -519) and TNF (-308) genes in relation to the risk of PD, and their associations with age of PD onset in a group of 316 patients, divided into two subgroups: Group 1: patients with early onset PD (EOPD), i.e. before 50 years of age (102 patients), and group 2: patients with onset of PD after 50 years of age comprising 214 subjects. Control samples were obtained from 300 randomly selected healthy individuals from the same geographical region with no signs of Parkinsonism as evaluated by a neurologist. PCR-RFLP methods were used for genotyping. No statistically significant differences between PD patients and controls were found in the frequency of a single locus of IL10 promoter. We found TNF -308A allele significantly more frequent in EOPD patients compared to the controls (p = 0.007). The overrepresentation of the A allele was reflected by a significant increase in AA homozygous individuals in EOPD patients compared to the controls (p = 0.0021). The results from our study revealed that the TNF -308AA genotype might increase the risk of early onset of PD. (c) 2008 Elsevier Ltd. All rights reserved.