Gene polymorphisms of the catalase, glutathione peroxidase 1,endothelial nitric oxide synthase in vitiligo

Vitiligo is a relatively common skin disease characterized by development of patchy depigmented macules. Several theories have been proposed about the pathogenesis of vitiligo, including autoimmune, neural and cytotoxic but the cause is still unknown. Previous studies of vitiliginous melanocytes showed that an imbalance between oxidative and antioxidative patterns. For this reason, we aim to investigate the polymorphisms of detoxification genes, including catalase (CAT) A/T promotor and T/C exon 9, glutathione peroxidase 1 (GPX 1) codon 200, endothelial nitric oxide synthase (eNOS) +894 and intron 4 VNTR (variable number of tandem repeat) in patients with vitiligo and healty controls groups by PCR-RFLP (Polymerase chain reaction-restriction fragment length polymorphism) method.. One hundred twenty-five patients with vitiligo and 100 healthy volunteers with no personal and family history of vitiligo were enrolled in the study. Then the data compared between the study groups. There were no significant differences in the polymorphisms of eNOS +894 and intron 4 VNTR genes, between vitiligo patients and healthy controls (p=0.001). TT genotype in catalase A/T promotor region are significantly increased in patients with vitiligo in comparison with controls. However, there were no significant differences in the polymorphisms of catalase T/C codon 389 in exon 9 gen, between vitiligo and controls. TT genotypes in GPX 1 codon 200 are significantly increased in patients with vitiligo in comparison with controls (p=0.027). When all gene polymorphisms were analyzed also according to the clinical types and family history of vitiligo there were no significant differences between these parameters. In conclusion, TT genotype of catalase A/T promotor region and GPX 1 codon 200 may be associated with vitiligo.Key Words: Vitiligo, gene polymorphism, CAT, GPX 1, eNOS