APC and neoplasm: Deletion of the 5q region in tumour D17, together with a somatic APC mutation, resulted in loss of APC. However, the deletion in tumour D8, previously found to carry a β-catenin gene mutation, was positioned at 5q14.3-q22.1, and encompass BACs directly centromeric to the APC gene but not those comprising the 5′ and 3′ end of the APC gene (RP11-3B10 and CTC-1554D6).