IGHG3 and common variable immunodeficiency: 26/39 subjects (66.7%) fulfilled the criteria of CVID, 2/39 had an IgG deficiency (5.1%), 9/39 an IgG subclass deficiency (mostly combined IgG1/IgG3) (23.1%), one person had a lymphoproliferative disorder and one subject developed a secondary humoral immunodeficiency after ocrelizumab treatment.