RB1 and neoplasm: Among the genes localized within deleted regions are well-established tumor suppressor genes including the cell cycle inhibitors CDKN2A and RB1 and the mTOR inhibitor TSC2. Consistent with LOH suggested by the high allelic frequencies for TP53 (p.R248Q) and APC (p.R790*) mutations, we confirmed segmental loss of -17p and -5q containing the wild-type TP53 and APC (p.E1554fs) alleles, respectively.