A meta-study in a population of pregnant women found that the risk of hypertension was significantly increased in the presence of high air pollution and mutations in the MTHFR gene (Yang, Yang & Shiao, 2018), and a study by Fu et al. (2018) in Chinese children confirmed that there was also an interaction between the MTHFR gene and the effect of obesity on hypertension. This evidence concerns the gene MTHFR and hypertensive disorder.