Infection with SARS-CoV-2 requires interaction between the viral surface protein, spike (S), and a host “receptor” protein, angiotensin-converting enzyme 2 (ACE2) [3], that is expressed on type II alveolar cells [4] and ciliated cells in the human airway epithelium (HAE) [5], making these cells potentially vulnerable to infection. The gene discussed is ACE2; the disease is infection.