This finding was consistent with MSH2-deficiency having driven tumorigenesis in this rectal cancer (germline c.2006T allele serving as the “first-hit” and somatic LOH of the wild-type c.2006G allele as the “second-hit”) with secondary loss of MSH6 expression as a consequence of its dependency on intact MSH2 as opposed to any involvement by the MSH6 c.3936_4001+8dup variant. The gene discussed is MSH6; the disease is rectal cancer.