Other antioxidant genes may undergo mutations, including polymorphisms in glutathione S-transferase (GST) M1, glutathione S-transferase pi 1 (GSTP1), superoxide dismutase 3 (SOD3), and epoxide hydrolase 1 (EPHX1), being related to lowering lung function and COPD severity [70]. Here, EPHX1 is linked to chronic obstructive pulmonary disease.