BRCA2 and pachyonychia congenita: In addition, PC cases are known to have a familial predisposition, and it is of high interest to investigate the association of NOD cases with familial predisposition and germline mutations in known PC genes such as Hereditary nonpolyposis colorectal cancer, BRCA2 (breast-ovarian), PALB2, Familial atypical multiple mole melanoma (p16), Familial pancreatitis (PRSS1), Peutz-Jeghers (STK11/LKB1), and ATM.