According to Tam et al.'s report [33], they focus on the impact of female sex hormones on chronic cigarette smoke-induced airway remodeling and emphysema in a mouse model of COPD; their results showed that small airway wall remodeling was increased in females but not males and was associated with increased distal airway resistance and activation of TGF-β1. This evidence concerns the gene TGFB1 and chronic obstructive pulmonary disease.