Our group was the first to show that soluble dimeric ACE2 protects mice from acute lung injury and acute respiratory distress syndrome (ARDS) (Imai et al, 2005), which triggered preclinical and clinical development of recombinant human soluble ACE2 (Treml et al, 2010; Haschke et al, 2013), termed APN01, for lung disease. This evidence concerns the gene ACE2 and lung disorder.