Two index cases had a single VUS in one MMR gene (MSH6 and PMS2), one index case had two VUS co-occurring in two genes (APC and BMPR1A) associated with hereditary colorectal polyposis and juvenile polyposis syndromes, respectively, and the remaining two index cases had a single VUS in other genes (NBN and ATM) not strictly correlated to hereditary predisposition to CRC. This evidence concerns the gene NBN and juvenile polyposis syndrome.