Studies have shown that oxidative stress-related markers, such as reactive oxygen species (ROS) and malondialdehyde (MDA) levels, are significantly elevated in smokers or patients with COPD, while antioxidants such as glutathione, superoxide dismutase (SOD) and catalase (CAT) are significantly reduced (9). The gene discussed is SOD1; the disease is chronic obstructive pulmonary disease.