As shown in Figure 1(a), serum Gd-IgA1 levels were significantly elevated in patients with IgAN (median, 6310 ng/ml; range, 1738–18621 ng/ml) compared to children with non-IgA glomerular diseases (2344 ng/ml, 407–12022 ng/ml) (p < 0.0001) and HCs (2239 ng/ml, 513–6166 ng/ml) (p < 0.0001). This evidence concerns the gene IGHA1 and glomerular disorder.