Association between IL-6 gene polymorphisms and susceptibility to Parkinson's disease

The multifunctional cytokine interleukin 6 (IL-6) and its single nucleotide polymorphisms (SNPs) may influence the risk of Parkinson's disease (PD).

To investigate the association between specific SNPs in the IL-6 gene and susceptibility to PD in the northern Chinese Han population.

A total of 800 Chinese Han subjects were enrolled in this case-control study, including 400 PD patients and 400 healthy controls. Peripheral blood of all subjects was collected for DNA extraction and genotyped for selected SNPs (rs1800796, rs1524107) using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

We found significant differences in the allele (C vs. G, p = 0.002) and CC genotype (p = 0.012) of rs1800796 in the PD group compared to the control group. In addition, significant differences were observed between the two groups in both dominant and additive models (p_dominant=0.046, p_additive=0.025). In further subgroup analysis, compared with the matched male control group, the frequency of CC genotype in male PD was higher (p = 0.035), and allele C may increase the risk of disease (p = 0.012). Similarly, when compared to the healthy control group, patients in the late-onset Parkinson's Disease (LOPD) group also exhibited a higher frequency of CC genotype and C allele (p_genotype = 0.015, p_alle = 0.004).

The rs1800796 polymorphism of the IL-6 gene may be associated with susceptibility to PD in the northern Chinese Han population.