In the meta-analysis, we confirmed the contribution of the MTHFR variant chr1:11753033:G:A to the predisposition to severe COVID-19, with a pooled OR of 1.21 (95%CI = 1.09–1.33) and the notable p = 4.34 × 10−14 in the weighted analysis (Table 4). This evidence concerns the gene MTHFR and COVID-19.