Association of selected variations in IL6, IL10, and IL17A genes with vitiligo

Abstract

Vitiligo is an autoimmune disease involving inflammatory damage to melanocytes. IL6, IL10, and IL17A cytokines play an important role in the development of vitiligo. However, it is not known whether this relationship translates into an association with the variations in the corresponding genes. The aim of the study was to determine the association of IL6 (rs1800795), IL10 (rs1800871), and IL17A (rs2275913) single nucleotide polymorphisms (SNPs) with vitiligo. The study was conducted using a case–control design involving vitiligo patients (n = 60) and healthy volunteers (n = 120). Genomic DNA was isolated from the peripheral blood samples of the study participants. The selected SNPs were genotyped using the polymerase chain reaction-restriction fragment length polymorphism method (PCR-RFLP). The chi-square test was used to evaluate the difference in the distribution of the alleles and genotypes between the two groups. The distribution of the three SNPs in the control group was in agreement with Hardy-Weinberg equilibrium. The minor allele frequencies of IL10 (rs1800871) and IL17A (rs2275913) SNPs were observed to be 60% and 34.2%, respectively, in vitiligo patients. The difference in the minor allele frequencies of both variants between the case and control groups was found to be statistically significant (p < 0.001, odds ratio = 2.3; 95% confidence interval (CI) 1.4–3.9). The minor allele frequency of the IL6 variant was observed to be 20.8% in vitiligo patients. The difference in the minor allele frequency between the case and control groups was not statistically significant (p = 0.3). These results imply that the IL10 (rs1800871) and IL17A (rs2275913) SNPs, but not the IL6 (rs1800795) SNP, are associated with vitiligo.