This is especially true for the associated SNVs in the non-coding regions, sometimes at a significant physical distance upstream or downstream from their nearest genes28. A candidate gene association study conducted on an English population comprising 165 patients and 304 controls found that rs2476601-T allele of PTPN22 was significantly associated with generalized vitiligo 29 however it is unclear how the gene PTPN22 contributes to vitiligo. The gene discussed is PTPN22; the disease is vitiligo.