LZTFL1 and COVID-19: Possible molecular mechanisms of the involvement of these genetic variants in the risk of developing severe COVID-19 may be associated with their regulation of the LZTFL1 gene (Leucine Zipper Transcription Factor Like 1), which regulates protein trafficking to the ciliary membrane, the violation of which may play an important role in weakened airway viral clearance in a patient with COVID-19 (Robinot et al., 2021).