However, in the skin of patients with progressive vitiligo, oxidative stress or intrinsic defects induce lower HSD17β1 expression in keratinocytes leading to the failure of keratinocytes in producing sufficient estradiol to protect melanocytes against oxidative stress, finally contributing to the destruction of melanocytes and vitiligo development (Figure 6c, right panel). This evidence concerns the gene HSD17B1 and vitiligo.