Immunodeficiency, Common Variable, 2, also known as hypogammaglobulinemia due to taci deficiency, is related to common variable immunodeficiency and primary agammaglobulinemia, and has symptoms including diarrhea An important gene associated with Immunodeficiency, Common Variable, 2 is TNFRSF13B (TNF Receptor Superfamily Member 13B), and among its related pathways/superpathways are Innate Immune System and Immune response Fc epsilon RI pathway. Affiliated tissues include b cells and t cells, and related phenotypes are recurrent otitis media and decreased circulating iga level