Those resulting in deficiency of either MALT1, BCL10, CARD11, or CARD9 lead to immunodeficiencies displaying increased susceptibility to a wide range of bacterial, viral and/or fungal infections8, whereas those resulting in gain-of-function properties in MALT1, CARD9, CARD11, and CARD14 lead to lymphoproliferative or autoimmune disorders9. Here, CARD11 is linked to immunodeficiency disease.