IFNL3 and COVID-19: IFNL3: Stevenson et al. (2021) claimed IFNL3 as one of the predictive markers for severe symptoms of COVID-19 based on analysis of serum chemokines and cytokines from COVID-19 patents, while another pharmacogenomic study did not find the potential of IFNL3 in modifying treatments (Sugiyama et al., 2020).