Finally, the mother possesses a variant in the TNFRSF13B gene, which encodes the transmembrane activator and calcium-modulating cyclophilin ligand interactor (TACI), a receptor crucial for B-cell function and immunoglobulin production and associated with common variable immunodeficiency (CVID) [24]. This evidence concerns the gene TNFRSF13B and common variable immunodeficiency.