Preliminary data from different cohorts of unselected Italian PC patients focusing on CDKN2A and BRCA1/2 showed a high prevalence of CDKN2A PVs, regardless of familial status [28] and of BRCA1/2 PVs—these latter being observed only in patients < 74 y [29]. The gene discussed is CDKN2A; the disease is pachyonychia congenita.