The same study, however, revealed that there are some potential markers to identify aggressive forms (HOXD8rc, CXCL14, SLC16A5rc, and GRASP) or progression (DOCKK2, HAPLN3, and FBXO30) of PC, but the methylation of some of these markers found in the tissue samples was not detected in ctDNA. The gene discussed is CXCL14; the disease is pachyonychia congenita.