The Point Mutation of Ras and p⁵³ Genes in Paraffin-embedded Gastric Cancer Tissues by PCR-RFLP Analysis

Polymerase chain reaction and restriction fragment length polymorphims (PCR-RFLP)analy-sis was used to determine the point mutation of ras and p⁵³ genes in formalin-fixed and paraffin-embedded gastric cancer tissue.The results showed that point mutations were detected in 13.6% (12 of 88) at codon 12 and 3.8%(3 of 80) at codon 61 of c-Ha-ras, 7.2%(5 of 69) at codon 12 of c-Ki-ras and 7.40o f5 of 68) at codon 248 of p⁵³ genes,but no point mutation was detected at codon 13 of c-Ki-ras and at codon 249 of p⁵³ genes.Our results indicate that PCR-RFLP tech-pique can be used to detect the point mutation of ras and p⁵³ genes in majority of formalinfixed and paraffin-embedded gastric cancer tissues.