In a related work, Rao et al. conducted a phenome-wide Mendelian randomization (MR) study examining an extensive amount of diseases, traits, and blood proteins and identified several ‘exposures’ including diabetes, breast cancer, lung cancer, inflammatory bowel disease, and smoking to increase ACE2 expression in normal lung tissue (Rao et al., 2020). This evidence concerns the gene ACE2 and lung cancer.