For hereditary cancer predisposition genes associated with high risk of cancer, such as BRCA1, BRCA2, CDH1, PTEN, and TP53, Clinical Genome (ClinGen) Variant Curation Expert Panels (VCEPs) have helped refine these general guidelines by incorporating gene-specific considerations,2,3,4,5 such as establishing expectations based on the standard penetrance associated with a gene of interest. This evidence concerns the gene CDH1 and cancer.