BACKGROUND

Vitiligo is a depigmentary disease characterized by loss of melanocytes from the skin and mucous membranes. The pathomechanism of vitiligo is still obscure. Inducible nitric oxide synthase (iNOS) produces very large amounts of nitric oxide (NO). Promotor polymorphisms within iNOS gene have been reported to be associated with overproduction of NO, which may induce melanocyte destruction.

AIM

The current study aimed at investigating the possible association between iNOS gene polymorphism (-954 G/C and Ex 16+14 C/T) and susceptibility to non-segmental vitiligo in a cohort of Egyptians.

METHODS

The study was conducted on 200 participants: 100 patients with vitiligo and 100 aged matched healthy controls. Polymerase chain reaction using restriction fragment length polymorphism method (PCR-RFLP) was used to identify the genotypes.

RESULTS

Our results showed that iNOS -954 G/C heteromutant genotype (GC) was associated with increased risk of vitiligo (OR = 3.35, 95% CI = 1.77-6.33), and the risk increased when confined to females (OR = 7.4, 95% CI = 2.80-19.40). iNOS Ex 16 + 14 C/T heteromutant genotype (CT) conferred two folds increased risk of vitiligo (OR = 2.47, 95% CI = 1.39-4.37). Furthermore, the risk of vitiligo increased when the heteromutant genotype of iNOS -954 G/C (GC) was co-inherited with the wild genotype of iNOS Ex16+14 C/T (CC) (OR = 23.2, 95% CI = 3.04-177.21).

CONCLUSIONS

Inducible nitric oxide synthase -954 G/C and Ex 16+14 C/T might be considered as genetic susceptibility markers for non-segmental vitiligo among Egyptians.