In this regard, Rouleau and colleagues [37] used an in-house array CGH platform to search for copy number imbalances in ten genes involved in hereditary breast and ovarian cancer including BRCA1, BRCA2, CHEK2, BARD1, ATM, RAD50, RAD51, BRIP1, RAP80 and PALB2. In a series of 472 patients, they found only three large rearrangements in BRCA1/2, two in CHEK2 and one intronic deletion in BRIP1. In our series, with the exception of RAP80, all genes were also evaluated for DNA copy number imbalances. The gene discussed is CHEK2; the disease is Hereditary breast and ovarian cancer syndrome.