Activating mutations in the k-ras gene in ulcerative-colitis and crohns-disease

Patients with ulcerative colitis (UC) and Crohn's disease have an increased risk for developing cancer of the colon. Mutations in the K-ras gene are relatively frequent in specimens from patients with sporadic colon cancer, but less frequent in cases of cancer complicating ulcerative colitis. In order to study the problem further we used the polymerase chain reaction (PCR) technique followed by a restriction fragment length polymorphism (RFLP) assay, to detect mutations at codon 12 of K-ras in biopsy specimens from patients with UC or Crohn's disease. Six among 27 patients (22.2%) with UC and 2 of the 19 patients (10.5%) with Crohn's disease examined, carried a mutation at codon 12 of K-ras. Our results indicate that mutations in K-ras may be a genetic marker that would reveal the predisposition to colon cancer among this group of patients.