GGT7 and chronic obstructive pulmonary disease: Two other genes involved in the glutathione metabolism pathway, CHAC1 and GGT7, were also found to be associated with four different aging outcomes (CHAC1 was associated with frailty index, diabetes, COPD, and BMI; GGT7 was associated with father’s age at death, endometrial cancer, and BMI) (Figure 4).