At both the genetic and genomic levels, many hypermethylated genes previously reported in PC studies were identified as hypermethylated DMRs in the present study, including LHX1, FOXE1, PAX6, BNIP3[30], ALPP, CEBPA[31], CACNA1G[32], CCND2[33], BAI1, NRN1, PENK, FAM84A, and ZNF415[6]. The gene discussed is CCND2; the disease is pachyonychia congenita.