TP53 and cancer: Despite National Comprehensive Cancer Network (NCCN) and NSO recommendations for genetic testing of CHEK2 and PALB2, in addition to BRCA1/2, for individuals with a >30% risk, the observed utilization and positive results for these and other cancer predisposition genes (P53, NOD2, NBS1, CDKN2A, PIK3CA) were unexpectedly low [8,33].