MTHFR and leukemia: Collectively, these studies indicate that genetic polymorphisms in MTHFR are widely associated with the occurrence and development of leukemia (Aly et al. 2014; Bănescu et al. 2015; Cwiklinska et al. 2020; Gutiérrez-Álvarez et al. 2016; Huang et al. 2015; Sazawal et al. 2014).