Consideration of GREM1 Gene in Hereditary Colon Cancer Genetic Testing

Hereditary mixed polyposis syndrome (HMPS1) is a rare inherited colon cancer syndrome caused by duplication of the GREM1 gene. HMPS1 has been described in Ashkenazi Jews, and affected patients present with variable numbers of adenomas and serrated class lesions, and sometimes juvenile or inflammatory polyps. However, clinical presentation of the syndrome is still poorly documented.

In the current report, researchers describe four families from Israel, all of whom had a 40kb duplication in a noncoding sequence near the GREM1 gene. The clinical profiles varied from that of a familial adenomatous polyposis (FAP)–like syndrome — with extensive polyposis, desmoid tumors, and duodenal cancer — to one with much smaller numbers of polyps presenting …