The Fc fragment neonatal receptor (FcRN) is found in the choroid plexus and microvascular endothelial cells33 and facilitates the transit of IgG across the luminal surface.34 It is composed of a heavy chain, Fc region of IgG-targeting receptor transporter (FcGRT), and a light chain, β-2-microglobulin.35 Acting in a pH-dependent manner, FcRN binds to IgG at an acidic pH and releases it at a neutral pH.36, 37 As a result, the expression of FcGRT may influence the abundance of antibodies in the brain in psychiatric disease. The gene discussed is FCGRT; the disease is psychiatric disorder.