Chandra et al., in an epigenome-wide DNA methylation study, found several differentially methylated loci, overlapped with different PSORS regions, involved in the regulation of pathogenetic gene expression, such as S100A9 (S100 calcium binding protein A9), SELENBP1 (selenium binding protein 1), CARD14 (caspase recruitment domain family member 14), KAZN (kazrin, periplakin interacting protein), and PTPN22 (protein tyrosine phosphatase non-receptor type 22), indicating the potential role of DNA methylation in regulating specific histopathological features commonly seen in psoriasis [80]. Here, PTPN22 is linked to psoriasis.