Folic acid is a water-soluble vitamin, also known as vitamin B9. In the folic acid metabolism pathway, single nucleotide polymorphisms (SNPs) of methylenetetrahydrofolate reductase (MTHFR) and methionine synthetase (MTRR) can affect the activity of MTHFR and MTRR enzymes and can affect Serum folate and homocysteine levels. It will lead to hypofolateemia and hyperhomopenic acidemia, thereby increasing the risk of neonatal birth defects, neural tube diseases and cardiovascular diseases.

  Folic acid gene testing can provide guidance for people who lack folic acid due to genetic factors to achieve precise medication; provide the basis for the onset of patients with hyperhomocysteinemia; define family genetic history, and provide guidance for eugenics and personalized medication.