For the MSH6 gene, only 1 out of 8 variants studied (13%) was found to have aberrant effects on protein function; for the PMS2 gene, 4 variants were analyzed and all (100%) seem to have a causative role in Lynch syndrome; for the MLH3 gene, however, functional assays have not identified any variant with certain pathogenetic significance; finally, for the MSH3 gene relevant functional studies have not yet been reported (https://www.insight-group.org). This evidence concerns the gene PMS2 and Lynch syndrome.