First, in July 2020 Xu et al. suggested the possibility that the course of SARS-CoV-2 may be more severe in C1-INH-HAE patients, and that the infection may aggravate HAE symptoms, or it may provoke angioedematous attacks in symptomless C1-INH-HAE patients23. The gene discussed is SERPING1; the disease is hereditary angioedema.