P. ChaksangchaichotP. PunyaritS. PetmitrMahidol UniversityPhramongkutklao College of Medicine2018-08-242018-08-242007-01-01Journal of Cancer Research and Clinical Oncology. Vol.133, No.1 (2007), 65-70017152162-s2.0-33751509283https://repository.li.mahidol.ac.th/handle/20.500.14594/24276Purpose: To detect the hMSH2, hMSH6 and hMLH1 DNA mismatch repair gene mutations and microsatellite instability in somatic colorectal cancer. Patients and methods: The mutations of hMSH2, hMSH6, and hMLH1 genes, including microsatellite instability of BAT-26, BAT-40, D2S123, D5S346 and D17S250 were analyzed in 31 patients with colorectal. Results: The results revealed that eight cases (25.8%) harbored mutations in DNA mismatch repair genes. Of these, five novel mutations including I237V in exon 4 of hMSH2, ins T at codon 1196 in exon 7 of hMSH6, and ins G at codon 154 in exon 6, N158H in exon 6, and del A at codon 257 in exon 9 of hMLH1 were identified. Moreover, several intronic polymorphisms, including c-g transversion at IVS-1 nt211 + 9 of hMSH2, del T in poly T track at IVS-6 nt3559-5, ATCT duplicate in IVS-7 nt 3642 + 35 and t-g transversion at IVS-10 nt4080 + 185 of hMSH6 were demonstrated in these patients. In addition, seven cases (22.5%) exhibited microsatellite instability (MSI). Conclusion: These results suggested that the inactivation of DNA mismatch repair genes and microsatellite instability may play a minor role in somatic colorectal cancer development. © 2006 Springer-Verlag.Mahidol UniversityBiochemistry, Genetics and Molecular BiologyMedicineArticleSCOPUS10.1007/s00432-006-0147-z