Chronic obstructive pulmonary disease (COPD) is an inflammatory lung disease that causes respiratory symptoms such as shortness of breath and is the fourth leading cause of death worldwide. While COPD affects both males and females, females, in general, have worse symptoms and more COPD complications compared to males. We still do not have a good understanding as to why COPD behaves differently in females versus males. COPD was thought to mainly affect elderly males who were cigarette smokers; thus, most of the research have focused on males rather than females. To shrink this gap in knowledge, it is necessary to include females in biomedical and clinical studies and investigate the biological reasons behind why sex might affect how COPD develops. We hypothesise that some of the genes associated with COPD have different effects on males and females. In this project we will use a patient’s genetic code and how their genes behave to determine sex-specific signatures in their lungs and airways, and then measure how these signatures can predict the development of future COPD. This project can potentially contribute to the improvement of COPD treatment (particularly in females) and to identify new therapeutic targets for COPD.