A multimodal approach of complementary techniques targeting primarily truncating, deletion and rearrangement mutations provides a robust screening protocol that identifies the vast majority of pathogenic germline APC gene mutations in FAP patients. Patients in whom no mutation is identified through this mutation protocol, may be sub-cohorts representing a different FAP pathogenesis including MYH associated polyposis and somatic cell mosaicism for APC gene mutations. (C) 2009 Elsevier Ltd. All rights reserved.