MT2A and infection: Notably, the GO analysis performed on DEGs between patients with persistent olfactory symptoms (Group 1) and patients who never experienced these symptoms (Group 3) after the infection revealed a statistically significant enrichment of genes involved in detoxification of inorganic compound (MT1E, MT1F, MT1G, MT1H and MT2A, Figure 5E, Supplementary Figure 8, Supplementary Table 12).