Polymorphisms of the Methylene Tetrahydrofolate Reductase and Susceptibility to Acute Lymphoblastic Leukemia in Children

Abstract

Background: Correlation between epigenetic factors and their effects on hematopoietic cells has led to a study of 2 common functional polymorphisms (C677T and A1298C) of 5,10methylene tetrahydrofolate reductase (MTHFR) enzyme. The aim of this study was to assess the individual and/or combined roles of these 2 polymorphisms in pediatric acute lymphoblastic leukemia (ALL). Methods: Using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analyses, we studied the frequencies of the C677T and A1298C MTHFR genotypes in 103 pediatric ALL patients and 160 age-sex matched controls. We calculated the odds ratio (OR) of MTHFR genotypes to determine if 1 or both of these polymorphisms may be associated with childhood ALL. Results: The T allele frequency for MTHFR 677C>T was 22.2% and 18.45% in controls and cases, respectively. The C allele frequency for MTHFR 1298 A>C was 40.65% and 40.72% in controls and cases, respectively. The OR for MTHFR 677CT was 1.08 (95%CI 0.58-1.95) and OR for MTHFR 677TT was 0.25 (95%CI 0.05-10.24). The OR for MTHFR 1298 AC was 0.57 (0.95% CI 0.57-1.95) and for MTHFR CC was 0.96 (0.95% CI 0.37-2.45). The OR for the combined heterozygous status (677CT and 1298AC) was 1.08 (95% CI 0.41-2.82). Conclusion: Our findings suggest that the MTHFR C677T and A1298C gene variants lack a major influence on the susceptibility for pediatric ALL. Another result was that the C allele frequency for MTHFR 1298 A>C was significantly higher than those reported for most Asian and European populations. The C677T prevalence seems to be similar to those reported in most Asian populations.