Background: A 40 kb ancestral germline duplication upstream of the GREM1 gene was reported in Ashkenazi families with hereditary mixed polyposis syndrome (HMPS).
Objective: Assess the contribution of the GREM1 mutation to familial colorectal cancer (CRC) in Ashkenazim.
Methods: Jewish Ashkenazi individuals (n = 472 155 males, 317 females) were genotyped for the GREM1 duplication, 194 with CRC, 131 had other cancer types (endometrial, pancreatic and ovarian) that show a syndromic association with CRC, and 147 were cancer-free with a suggestive family history of CRC.
Results: One mutation carrier was found who fulfills the Amsterdam criteria for Lynch Syndrome (LS). The prevalence of this mutation amongst LS Ashkenazim is 0·7%.
Conclusion: If validated in additional studies it seems rational to recommend to look for the GREM1 founder mutation in Ashkenazi individuals with multiple colorectal polyps and/or fulfill the criteria for LS.