Altered serum levels of the soluble isoforms of two TNF receptors, tumor necrosis factor receptor TNFR1 (TNFRSF1A) and TNFR2 (TNFRSF1B), are linked to inflammatory signaling, neuronal cell death, and regeneration, and altered in patients with ND [29, 32, 81–97]. The gene discussed is TNFRSF1B; the disease is Norrie disease.