So far, several monogenic defects such as ICOS, CD19, CD20, CD21, CD27, CD81, IL21, IL21R, LRBA, PRKCD, RAC2, TNFSF12, CTLA4, PLCG2, NFKB1, NFKB2, PIK3CD, PIK3R1, VAV1, BLK, IKZF1, IRF2BP2, as well as mutations in TNFRSF13B and TNFRSF13C have been identified in CVID (1, 5, 6). The gene discussed is NFKB1; the disease is common variable immunodeficiency.