TNFRSF13B and common variable immunodeficiency: Such digenic patients can only be identified by NGS (16, 54) and are a strong argument for sequencing both groups of genes, either causing CVID-like disorders (NFKB1, NFKB2, etc.)or those modifying the severity of CVID, such as TNFRSF13B/ TACI (19, 55).