On admission, there were higher serum concentrations of tumor necrosis factor α (TNFα) (p < 0.001), interleukin 1 β (IL-1β) (p < 0.001), pentraxin 3 (PTX3) (p < 0.001), resistin (p = 0.032), and lower concentrations of adiponectin (p < 0.001) between the severe COVID-19 and the non-severe patients. This evidence concerns the gene RETN and COVID-19.