title: IgG subclass deficiency and chronic fatigue syndrome.
mesh_terms: D002908:Chronic Disease; D005221:Fatigue / Q000276:immunology*; D006801:Humans; D017099:IgG Deficiency; D007074:Immunoglobulin G / Q000145:classification; D013577:Syndrome
chemical_list: D007074:Immunoglobulin G