In particular, germline or somatic mutations of BRCA1, BRCA2, PALB2, ATM, and CHEK2 have been reported in 20% of PDAC, while a deficiency of HRR genes was documented in 15.4% of PC and ATM mutations in 9–18% of PC [19,20,21]. Here, BRCA1 is linked to pachyonychia congenita.