Sex-stratified analysis (Supplementary Table S3) showed that rs17713054 SLC6A20-LZTFL1 elevates the risk of severe COVID-19 both in males (OR = 1.91, 95% CI = 1.12–3.26, p = 0.02) and females (OR = 1.63, 95% CI = 1.03–2.58, p = 0.04); additionally, we found that rs12585036 ATP11A lowers the risk of severe COVID-19 in males (protective allele T; OR = 0.51, 95% CI = 0.32–0.83, p = 0.004). This evidence concerns the gene LZTFL1 and COVID-19.