In conclusion, our findings indicate that MBIs seems to be associated with significant improvements in the ERP amplitudes in patients with ADHD, in the methylation of serotonin transporter genes in patients with PTSD, in the salivary levels of IL-6 and TNF-α in participants with depressive symptoms and in the blood levels of ACTH, IL-6 and TNF-α in patients with GAD. This evidence concerns the gene TNF and attention deficit-hyperactivity disorder.