Serum chemerin and omentin concentrations were significantly decreased in COVID-19 patients compared to healthy volunteers (271.0 [236.4–309.2] vs. 373.0 [363.1–392.3] ng/ml; p < 0.001 and 482.1 [327.4–665.2] vs. 814.3 [435.3–1148.5] ng/ml; p = 0.01, respectively). Here, RARRES2 is linked to COVID-19.