APC and cancer: These functionally converging and regionally mosaic patterns were also observed for APC, where three regional biopsies of MSS3 harbored one nonsense APC mutation, arm-level and focal 5q losses, respectively, along with a public out-of-frame indel of APC. In addition, two region-specific hotspot missense mutations were observed for SMARCA4 (MSS1) and similar representation was observed for a cancer-related gene of FBXW7 (one nonsense and one hotspot mutation in MSS2).