We conducted a hospital-based prevalent case-control study in a Japanese population (cases=103, controls=487) to ascertain the previous report about the association between the polymorphism in exon 13 of the hMSH2 gene (gIVS 12-6T-->C) and the risk of non-Hodgkin lymphoma in an Ecuadorian population. When the TT genotype was defined as the reference, none of the CT genotypes (OR=1.52; 95% CI, 0.97-2.37), CC genotypes (OR=1.06, 95% CI, 0.44-2.54), or CT and CC genotypes combined together (OR=1.44, 95% CI, 0.94-2.23) demonstrated significant OR. Further investigations with sufficiently larger populations and in other ethnicities are required to verify this association.