Objective: The aim of the present study was to investigate the association of single-nucleotide polymorphisms (SNPs) in the macrophage migration inhibiting factor (MIF ), interferon-induced Helicase C domain 1 (IFIH1 ), interleukin-6 (IL6 ) genes, circulating levels with non-segmental vitiligo (NSV) susceptibility in the Chinese population, and to analyze the relationships between gene polymorphisms and clinical characteristics of vitiligo.
Methods: In this study, genotyping was conducted in 155 patients with NSV and 117 unaffected controls using polymerase chain reaction and snapshot technique. Serum concentrations were determined by ELISA kit.
Results: There were strong associations between IFIH1 H843R and IL6 -572G/C polymorphisms and NSV susceptibility (p = 0.013; p = 0.009). In contrast to previous studies, we found no significant difference in the MIF -173G/C polymorphism between the two groups. In addition, the frequency of allelic distribution for MIF -173G/C in patients with active NSV was significantly higher than stable NSV (p = 0.011), and IFIH1 H843R with early-onset (≤ 20), active or family history of NSV was significantly higher than late-onset (> 20), stable or no family history of NSV (p = 0.033; p = 0.045; p = 0.039). Serum concentrations of MIF were higher in patients with active NSV, serum IFIH1 and IL6 concentrations were related to the presence of polymorphisms in patients with NSV (p = 0.009; p = 0.011).
Conclusion: Our results suggested that IFIH1 H843R and IL6 -572G/C gene polymorphisms and expression levels are obviously correlated with the onset of NSV. MIF -173G/C allele and serum concentrations may be associated with active NSV, and IFIH1 H843R allele may be associated with youth, active or family history of NSV.
Keywords: vitiligo, MIF , IFIH1 , IL6 , single nucleotide polymorphism