Association between single nucleotide polymorphisms in the hMSH3 gene and sporadic colon cancer with microsatellite instability

The association between three single nucleotide polymorphisms (SNPs) in the hMSH3 gene and sporadic colon cancer with microsatellite instability (MSI) was analyzed. Of the three SNPs observed in this population, SNPs at resid ues 235 and 693 were novel, while that at residue 3133 was previously descr ibed. The SNPs at residues 235 and 3133 caused amino acid substitutions, V7 9I and T1045A. respectively. Wt analyzed the allele frequencies of the thre e SNPs in samples from 19 patients with sporadic colon cancer with MSI and 90 healthy controls. We found that the V79 allele frequency was significant ly higher in the tumor samples than in controls. In addition, the frequency of the G693 allele showed a higher trend in the tumor samples than in cont rols. These results indicated that some SNPs in the hMSH3 gene were associa ted with colon cancer with MSI.