TYMS 2R3R polymorphism and DPYD [IVS]14+1G>A mutation genes in Mexican colorectal cancer patients

Objetive: To examine the association between TYMS 2R3R polymorphism and DPYD [IVS]14+1G>A mutation by comparing healthy subjects with colorectal cancer (CRC) patients from a Mexican population. Method: The genotyping of the 2R/3R was performed by polymerase chain reaction (PCR) and -[IVS]14+1G>A mutation by real-time PCR analysis. Results: The observed frequencies of the TYMS 2R3R polymorphism and the -[IVS]14+1G>A mutation on DPYD did not indicate an increased risk for CRC (p>0.05). An association between genotype and disease was evident. The distributions of the 2R/2R genotype and hematological toxicity (adjusted OR 2.26, 95% CI 1.54-4.45, p=0.0259), heterozygous (2R/3R) with tumor stage III-IV (OR 2.4, 95% CI 1.1-4.4, p=0.035) and 2R/2R-2R/3R in non-chemotherapy response CRC patients with hematological (OR 3.11, 95% CI 1.18-8.2, p=0.035) and gastric toxicities (OR 2.3, 95% CI 1.21-4.4, p=0.014) confirmed that this factor may contribute significantly to CRC susceptibility. Conclusion: TYMS 2R3R polymorphism and the -[IVS]14+1G>A mutation on DPYD was not associated with susceptibility for CRC. However, the genotypes 2R/2R and 2R/3R of TYMS polymorphism could contribute significantly to hematological and gastric toxicity in CRC patients in this sample population.