In many countries, variant screening of susceptibility genes (BRCA1, BRCA2, PALB2, TP53, STK11, CDH1, PTEN, ATM, BARD1, RAD51C, RAD51D and CHEK2 for BC and the DNA mismatch-repair genes, MLH1, MSH2, MSH6, and PMS2, in Lynch syndrome for EC) are offered in clinical practice of high-risk women [8,9,10]. The gene discussed is BRCA1; the disease is breast cancer.