Posttreatment at 13 years of age, she developed persistent hypogammaglobulinemia with low levels of immunoglobulin A (IgA; 0.16 g/L), immunoglobulin M (<0.04 g/L), and immunoglobulin G (IgG; 3.6 g/L) and recurrent upper respiratory infections, leading to a diagnosis of CVID. The gene discussed is CD79A; the disease is common variable immunodeficiency.