[Detection of G-->T mutation at codon 12 of H-ras oncogenes in gastric cancers with polymerase chain reaction and oligodeoxynucleotide(PCR-ODN)].

DNA was extracted from paraffin-embedded gastric cancer tissues, and the possibility of G-->T mutations present at codon 12 of H-ras oncogenes was detected in Chinese gastric cancer patients with polymerase chain reaction (PCR) and oligodeoxynucleotide (ODN) probe hybridization. Point mutations were identified in 5 of 17 gastric cancer cases (29.4%), and in none of 7 gastric ulcer cases. These results indicate that G-->T mutations at codon 12 of H-ras oncogene may play a role in activating the oncogenes in gastric cancers.