Recent findings indicate the potential role of hydrogen sulfide (H2S) as a fundamental host defense factor against SARS-CoV-2 infection [17], showing that low serum levels of H2S inversely correlate with inflammatory biomarkers such as IL-6 and C-reactive protein (CRP), and also associated with a poor prognosis in severe COVID-19 patients [18]. The gene discussed is CRP; the disease is COVID-19.