Spatial genetic ITH measured in multiple individual crypts from 10 FAP microadenomas. Analysisrevealed two clones carrying different somatic adenomatous polyposis coil (APC) mutations inaddition to the foundingAPC mutation, therefore indicating a polyclonal origin. Phylogeneticanalysis using limited genetic markers (APC,KRAS, andTP53 mutations; LOH of 5p, 17p, and18q) in 11 sporadic carcinoma-in-adenomas revealed different subclones between regions ofcarcinoma and low- and high-grade dysplasia. The gene discussed is KRAS; the disease is adenoma.