MTHFR-C677T Gene Polymorphism and Susceptibility to Acute Lymphoblastic Leukemia in Children: A Meta-Analysis.

Background: The association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism (rs1801133) and childhood acute lymphoblastic leukemia (ALL) is inconsistent.
Objective: To explore the relationship between MTHFR-C677T polymorphism and susceptibility to childhood ALL.
Methods: PubMed, EMBASE, Web of Science, CNKI, Wanfang, VIP, and other databases were searched from the establishment of the database to November 2019, and all the case-control studies that met the inclusion criteria were collected. Stata 15.0 was used for meta-analysis, with calculation of the odds ratio (OR) of the relationship between MTHFR-C677T polymorphism and childhood ALL susceptibility. Ethnicity was analyzed by subgroup analysis.
Results: A total of 26 studies were included in this meta-analysis, including 4,682 children with ALL and 7144 controls. The results showed that there was no significant difference in the comparison of population of allele model, dominant gene model, recessive gene model, homozygous gene model, heterozygous gene model, and the comparison of Caucasian children. The results of the Asian child analysis suggested that the combined OR of the dominant gene model (CC + CT versus TT), homozygous model (CC versus TT) and heterozygous model (CT versus TT) was 1.32 (95% confidence interval [CI]: 1.03-1.70), 1.37 (95% CI: 1.02-1.84), and 1.27 (95% CI: 1.01-1.59), respectively, with statistically significant differences. However, there was no significant difference between the allele model and recessive gene model among Asian children.
Conclusion: The MTHFR C677T polymorphism is related to ALL in children, especially in Asian children. CC + CT, CC, and CT genotypes can increase the risk of ALL, but no association has been found in Caucasian children.