A possible explanation for this phenomenon resides in the low levels of antioxidants, including catalase (CAT), glutathione peroxidase (GPx), glucose-6-phosphate dehydrogenase (G6PD) and superoxide dismutase (SOD), in skin lesions and serum of patients with vitiligo (Yildirim et al., 2003; Hazneci et al., 2005; Shajil and Begum, 2006; Laddha et al., 2013; Agrawal et al., 2015). This evidence concerns the gene CAT and vitiligo.