GREM1 and neoplasm: It is also worth noting that although Davis et al [4] did not find any bowel abnormality in the absence of other genetic mutations, they observed a reduced polyp burden following Grem1 depletion in mice carrying a tumour‐promoting mutation of the adenomatous polyposis coli locus, a finding compatible with the role for Grem1 in the regulation of epithelial proliferation that we found.