Frequency and clinicopathology associations of K-ras mutations in colorectal cancer in a northeast Mexican population

Activation of the ras family gene has been implicated in colorectal tumorig enesis, K-ras being the most frequently altered gene. The frequency of K-ra s codon 12, 13 and 61 point mutations in patients with colorectal neoplasia s was examined. We employed a polymerase chain reaction-restriction fragmen t length polymorphism assay and single-strand conformational polymorphism t o detect mutations. We found that point mutations at codons 12 and 13 were present in 53% and 39% of the tumors, respectively, but none at codon 61, T hese results agree with previous reports. Point mutations were more frequen t in adenomas than in carcinomas, with villous adenomas presenting a higher incidence of mutations than other adenomas, The association between clinic al and histopathological parameters was investigated. Our study is the begi nning of a new research line in molecular epidemiology of colorectal cancer and is the first to be carried out in one part of the Mexican population. Copyright (C) 2000 S. Karger AG, Basel.