Association of CAT 389 T/C and – 89 T/A gene polymorphisms with vitiligo: relation with oxidative stress

Background Vitiligo is a common, chronic skin disease characterized by selective destruction of melanocytes. The worldwide disease prevalence ranges from 0.1 to 8.8% with no sex preference. The catalase (CAT) gene expression and polymorphism affect the CAT level and activity. Association between some CAT gene polymorphisms and vitiligo has been reported; however, the results were inconsistent. Objective To analyze whether CAT 389 T/C and – 89 T/A gene polymorphisms are associated with vitiligo and to investigate their effect on the serum level of CAT and malondialdehyde (MDA) in those patients. Patients and methods Typing of CAT 389 T/C and CAT – 89 T/A using PCR-restriction fragment length polymorphism and evaluation of serum levels of CAT and MDA were carried out for 106 vitiligo patients and 95 healthy controls. Results Nonsignificant differences were found between patients and healthy controls for the allele and genotype frequencies of CAT 389 and CAT – 89 except for the increased frequency of T allele of CAT 389 in patients with vitilgo (P= 0.02 and Pc= 0.04). The frequency of combined CCAT genotype was increased in healthy controls versus that in the patients (P= 0.007 and Pc =0.014). In vitiligo patients, the serum level of CAT was lower and the level of MDA was higher compared with healthy controls (Pr0.001). No significant associations were found between the genotypes and haplotypes of the studied single-nucleotide polymorphisms and disease activity, disease extent, serum levels of CAT, and MDA. Conclusion The T allele of CAT 389 may be a susceptibility risk factor for vitiligo and the combined CCAT genotype may be protective in the studied sample of patients. Decreased levels of CAT with increased levels of MDA may indicate increased oxidative stress in nonsegmental vitiligo patients.