Retrospective analysis of hyponatremia occurrence in COVID-19 patients during the first pandemic period demonstrated a prevalence of 22.9% at hospital admission, a worse respiratory performance (evaluated as P/F, i.e., the ratio of the partial pressure of oxygen in arterial blood PaO2 to the inspired oxygen fraction FiO2), and higher IL-6 levels in hyponatremic rather than in normonatremic hospitalized patients [43]. The gene discussed is IL6; the disease is Hyponatremia.