For example, the patients of chronic fatigue syndrome (CFS) have shown significant variations in the expression of genes encoding miRNAs that regulate cytotoxicity, cytokine secretion, and apoptosis, closely related to the high expression of immunoinflammatory genes encoding tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and COX-2 in adolescent patients of CFS (Brenu et al., 2014; Deumer et al., 2021). The gene discussed is TNF; the disease is myalgic encephalomeyelitis/chronic fatigue syndrome.