In order to determine whether this could be due to an inhibition of miRNA biogenesis during severe COVID-19, we compared mRNA expression of genes involved in miRNA biogenesis, namely AGO2, DICER1, DGCR8, DROSHA, and XPO5, in nasopharyngeal swabs of severe and non-severe COVID-19 patients and controls. The gene discussed is XPO5; the disease is COVID-19.