Final, except for age, BMI and cigarette smoking, other factors including gene polymorphisms (e.g., arsenic 3-methyltransferase; GSTO1 and GSTO2 of glutathione S-transferase family) and nutrient intake (e.g., folate, vitamin B12 and vitamin B6) are also reported to be able to affect the arsenic methylation capacity and thus may influence the susceptibility to arsenic-induced hypertension. Here, GSTO1 is linked to hypertensive disorder.