2.4. Brain-Derived Neurotrophic Factor (BDNF), 5-Methylcytosine (5mC), and 5-Hydroximethylcytosine (5hmC) in the Non-Lesional Epidermis Showed Psoriasis-Severity-Associated Reduced Signal and Nuclear Expression Pattern of MECP2 Was Also Altered in Psoriatic Non-Lesional Versus Healthy Skin. The gene discussed is BDNF; the disease is psoriasis.