Mutation analysis of mitochondrial DNA in colorectal carcinoma tissues by silverª²staining PCRª²SSCP

    YAN Li, XIAO Bing, SONG Weiª²Bing, GENG Yan, LAI Zhuoª²Sheng

    Institute of Digestive Diseases, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China

    ¡¾Abstract¡¿ AIM: To analyze the mutations of mitochondrial DNA in colorectal carcinoma tissues. METHODS: Sliverª²staining Polymerase Chain Reactionª²Single Strand Conformation Polymorphism (PCRª²SSCP) technique and sequence analysis were used to detect the point mutation changes on the Dª²loop region in mitochondrial DNA in 40 colorectal carcinomas together with the adjacent normal tissues. RESULTS: Among the 40 colorectal carcinomas, point mutations were found in 7 colorectal carcinoma tissues with the mutation rate of 18% (7/40). Among the 9 point mutations, 3 point mutations were found in a colorectal carcinoma of Dukes¬ð stage D and the other 6 point mutations were found in 6 colorectal carcinomas of Dukes¬ð stage C. C to T mutation at np498 and at np16298 were found in 7 colorectal carcinomas with point mutations. CONCLUSION: A certain degree of point mutations is found in the Dª²loop region of mitochondrial DNA in colorectal carcinoma tissues, and the occurrence of mutations may be associated with colorectal carcinoma suscepª²tibility and malignant grade, but whether the mutations have carcinogenicity needs further study. ......