Association between an HLA-G 14 bp insertion/deletion polymorphism and non-segmental vitiligo in the Korean population

Abstract

Vitiligo is a pigmentary skin disorder characterized by the chronic and progressive loss of melanocytes. Although the etiology of vitiligo is still unknown, several theories have been proposed to explain the pathogenesis of vitiligo including autoimmune, neural, self-destruction, oxidative stress, and genetic theories. Human leukocyte antigen (HLA)-G is a nonclassic, major histocompatibility complex class I molecule that plays an important role in suppression of the immune response. Several recent studies have provided evidence that a 14 bp insertion (INS)/deletion (DEL) polymorphism in the HLA-G gene might be associated with autoimmune disease. Our aim in this study was to determine whether the 14 bp INS/DEL polymorphism in the HLA-G gene contributes to the risk of developing non-segmental vitiligo (NSV) in the Korean population. We conducted a case-control association study of 192 NSV patients and 491 matched, unaffected controls. The HLA-G 14bp INS/DEL polymorphism was analyzed by gene scan after amplification using the polymerase chain reaction. Genotype frequencies for the 14bpINS/DEL were different between the vitiligo group and Korean control group. The proportion of subjects with a homozygote 14bpINS/14bpINS genotype was significantly higher in the vitiligo group compared with the control group (7.1 vs. 3.5 %, OR 2.25, 95 % CI 1.06-4.76, p = 0.039 in the recessive model). Our results suggest that the HLA-G 14bpINS/DEL polymorphism is associated with the development of NSV in the Korean population.