IgA nephropathy (IgAN) is one of the most frequently diagnosed primary glomerulonephritis, characterized by deposition of IgA-based immunocomplex (IgA-IC) in the glomerular mesangial region.(1) IgAN is common in Asian countries including Japan, where IgAN is the highest cause leading to end-stage renal disease followed by diabetic kidney disease. The gene discussed is CD79A; the disease is diabetic kidney disease.