After the Bonferroni correction, the stratified analysis found that MX1 rs17000900 CA + AA genotype was related to a reduced risk of severe COVID-19 compared to the CC genotype in males (P = 0.001, OR = 0.050, 95%CI = 0.008–0.316), but it was not significant in females (Table 4 and Supplementary Table 4). The gene discussed is MX1; the disease is COVID-19.