MSH5 and common variable immunodeficiency: In contrast, mutations in other genes such as TNFRSF13B, which encodes Transmembrane Activator Calcium Modulator and Cyclophilin Ligand Interactor (TACI), MutS homolog 5 (MSH5) and TNFRSF13C, which encodes B-cell activating factor receptor (BAFFR), predispose to, but do not solely underlie CVID.