According to the registry of the National Familial Pancreas Tumor Registry (NFPTR), the risk of PC was 6.8‐fold higher in the relatives of cases with familial PC, and 2.4‐fold higher in relatives of cases with sporadic PC.31 It has been reported that BRCA2, PALB2, and ataxia telangiectasia mutated germ‐line mutations are most frequently identified in familial PC cases.32, 33, 34 In July 2013 in Japan, JPS established the familial PC registry for early diagnosis, and already started this registry in 2015. The gene discussed is BRCA2; the disease is pachyonychia congenita.