Vitamin D Receptor Gene Polymorphisms and Association with Vitiligo in Indonesian Population.

INTRODUCTION: Vitiligo is an acquired depigmenting skin disorder due to the loss of melanocyte function in the epidermis and hair follicles. The pathogenesis of vitiligo is multifactorial, with genetics being a predisposing factor. Previous studies had varying results regarding whether or not polymorphisms of vitamin D receptor ( VDR ) gene are associated with the risk of vitiligo in specific populations. This study investigated the association between three frequently analyzed VDR gene polymorphisms ( ApaI, BsmI, TaqI ) and susceptibility to vitiligo in Indonesian population.

METHODS: Thirty-four vitiligo patients and 34 age- and sex-matched healthy subjects aged ≥18 years old were recruited in the Dermatology and Venereology Outpatient Clinic of Dr. Hasan Sadikin General Hospital, Bandung, Indonesia. Genomic deoxyribonucleic acid (DNA) was extracted from the peripheral blood using a DNA isolation kit. VDR gene polymorphisms ( ApaI, BsmI, and TaqI ) were investigated using the polymerase chain reaction-restriction-fragment length polymorphism method. The differences of genotype distributions and allele frequencies were statistically compared between case and control groups using Chi-square test.

RESULTS: VDR gene polymorphisms were identified in 68 participants, consisting of Aa (n = 14), aa (n = 20), Bb (n = 15), bb (n = 19), and TT (n = 34) genotypes in the case group. In the control group, Aa (n = 6), aa (n = 28), Bb (n = 17), bb (n = 17), and TT (n = 34) genotypes were identified. However, only subjects with ApaI Aa genotype polymorphism had a 3.267-fold increased risk of developing vitiligo.

CONCLUSION: This study showed that ApaI Aa genotype polymorphism of the VDR gene increases the risk of vitiligo in Indonesian population.