On the other hand, serum IgA levels were also considered normal for specific ages in each group, however, group 1 (median 133 mg/dL, IQR = 71 – 173) were significantly lower than the serum levels of DS children without infection (median 149.5 mg/dL, IQR = 119–183) with p = 0.0020. The gene discussed is CD79A; the disease is infection.