COVID-19 patients expressing rs2285666 mainly display significant increase in ALT (p = 0.0315), AST(p = 0.0261), Hb (p = 0.02), ALC (p = 0.039), creatinine (p = 0.008), and BUN (p = 0.0027) blood levels (Fig. 7a). This evidence concerns the gene GSTM1 and COVID-19.