Identification of genotypes and allelic frequencies of vitamin D receptor gene polymorphism (TaqI) in egyptian melasma patients

Iman Seleit, Ola Ahmed Bakry, Eman Masoud, Shaimaa Nabil

Indian Dermatology Online Journal 2017 8(6):443-448

Background: Melasma is a characteristic pattern of facial hyperpigmentation, occurring primarily on the forehead, cheeks, and chin, in a mask-like distribution. The pathogenesis of melasma is not fully understood. Vitamin D plays a role in skin pigmentation. It exerts its effect through vitamin D receptor (VDR), which is expressed in variable cells including normal melanocytes. Aim and Objective: The aim of the current work was to investigate if VDR gene polymorphism (TaqI) confers susceptibility to melasma in Egyptian patients. Materials and Methods: A total of 45 female patients with melasma were recruited and 50 healthy subjects that were matched on age, sex, body mass index, and skin phototype, were included as a control group.TaqI polymorphism was investigated using restriction fragment length polymorphism polymerase chain reaction (RFLP PCR). Results: Presence of (t) allele and (tt) genotype was significantly associated with melasma cases compared with control group (P < 0.001 for both). No significant association was found between (tt) genotype or (t) allele and clinical data of the studied cases. Conclusion: TaqI polymorphism is associated with melasma. Further, large-scale studies are recommended to underscore and validate the current findings. It is also necessary for future studies to extend the research to other populations and ethnicities. Investigating other VDR gene polymorphisms in melasma is also warranted. Since melasma is a multifactorial disease, gene–gene and gene–environment interactions should be considered in future genetic-epidemiologic researches to apply more comprehensive insight into the role of VDR gene in its pathogenesis.