In the previously mentioned study by Coric [42] and collaborators from 2021, six genes were studied: GSTP1, GSTM3, GSTM1, GSTT1, and GSTA1. They found that carriers of the heterozygous GSTP1 IleVal (rs1695) genotype were less likely to develop COVID-19 (OR 0.66, 95% IC 0.44–0.98, p = 0.042), as were carriers of GSTP1*Val (rs1138272) allele in individuals carrying at least one Ala/Val allele (OR 0.63, 95% CI 0.41–0.99, p = 0.039), and the Val/Val genotype (OR 0.08, 95% CI 0.10–0.64, p = 0.017). Here, GSTP1 is linked to COVID-19.