APC and colorectal carcinoma: To test this notion, we analysed 85 Israeli patients with either early onset (< 50 years at diagnosis) or familial CRC for harbouring mutations within the relevant APC gene regions: exons 1–5, exon 9 and a region within exon 15 (spanning nucleotides c.3900 to c.4034; codons 1294 to 1338) using denaturing gradient gel electrophoresis (DGGE), and all of exon 15 employing protein truncation test (PTT).