IGHA1 and hyperinsulinemic hypoglycemia, familial, 4: Pathogenetic IgA only deposit in the mesangial areas of the glomerulus, whereas deposits are rare to find in podocytes or renal tubular epithelial cells, which suggests that IgA receptors are responsible for mesangial cell proliferation induced by galactose-deficiency IgA1 (Lai et al., 2016).