Their findings provide the characterization of the intestinal stem cell by lineage tracing using the expression of a single marker gene, LGR5. 21 In another study, Barker et al.21 demonstrated in a mouse model that LGR5-positive stem cells are the cells of origin of intestinal tumors by introducing adenomatous polyposis coli mutations into LGR5-positive stem cells, which stimulated adenoma formation in the small intestine and colon.22 These data suggest that LGR5 has an important role in colon cancer tumorigenesis. This evidence concerns the gene LGR5 and intestinal neoplasm.