To detect the effect of FER rs4957796 on the 90-day outcome of ARDS and the dependence on ARDS severity (mild, moderate, and severe), Kaplan-Meier survival analysis was performed for the 90-day survival in these three groups of patients (Fig. 1); FER rs4957796 affected the 90-day survival exclusively among patients with severe ARDS; patients with severe ARDS who were C-allele carriers showed a lower 90-day mortality rate than TT-homozygous patients (p = 0.0144) (Fig. 1). This evidence concerns the gene FER and acute respiratory distress syndrome.