[Determination of K-ras gene mutation in colorectal cancer tissue by capillary electrophoresis]

The codons 12/13 of K-ras genomic DNA from 76 colorectal cancer tissues and normal tissues were amplified by PCR. The amplified 152 samples were purified, denatured, and then detected using capillary electrophoresis (CE)-laser induced fluorescence (LIF) with single-strand conformation polymorphism (SSCP). The abnormal samples were further confirmed by direct-sequencing. The 30 patients of the 76 colorectal cancer patients were found gene mutation, of which the results of base G --> A point mutation were confirmed by the gene sequence. To detect K-ras gene mutation that has important role in clinical forecast, diagnosis, therapy and prognosis, the CE-LIF with SSCP was applied for detecting K-ras gene. It becomes a promising tool to analyse K-ras gene mutation in the clinical diagnosis and therapy of colorectal cancer tissue.