A genome-wide linkage analysis detected seven alleged vitiligo susceptibility loci, of which five have been associated with a causal gene: FOXD3 (Forkhead Box D3), NLRP1 (NLR family pyrin domain containing 1), PDGFRA (Platelet-Derived Growth Factor Receptor Alpha), HLA (human leukocyte antigen), and XBP1 (X-box binding protein 1) [22]. This evidence concerns the gene XBP1 and vitiligo.