GSTM3 and COVID-19: As for GSTM3 polymorphism, carriers of GSTM3 AC genotype had significantly lower odds of developing COVID-19 compared to individuals with GSTM3 AA genotype (OR = 0.60, 95%CI = 0.38–0.96, p = 0.033), while homozygous carriers of GSTM3*C allele had 1.7-fold increased COVID-19 odds but with borderline significance (OR = 1.71, 95%CI = 0.99–2.95, p = 0.053).