BRCA1 and pachyonychia congenita: The mutational screening of the investigated study population showed that 26 (7.4%) out of 352 patients with MBC, PCa, PC or melanoma harboured germline BRCA PVs (BRCA-positive), whereas 9 (2.6%) probands were carriers of germline BRCA1/2 VUS (class III), and 317 (90%) subjects carried a germline BRCA1/2 benign/likely benign variants (BRCA-w.