Furthermore, previous epidemiologic studies show that functional non-synonymous single nucleotide polymorphism (SNPs) of the MTHFD1 gene, such as MTHFD1 rs2236225 (G1958A; R653Q) and MTHFD1 rs1950902 (C401T; R134K), are associated with an increased risk of CHD, albeit the associations are controversial (14, 16, 17). The gene discussed is MTHFD1; the disease is coronary artery disorder.