A kidney biopsy showed mild global glomerulosclerosis by light microscopy along with chronic tubulointerstitial disease (not shown), weak segmental IgA deposition by immunofluorescence (Fig. 1e) and GBM alterations by electron microscopy with areas of thickening or thinning, multilamellation and intramembranous granular particles (Fig. 1f). The gene discussed is CD79A; the disease is glomerulosclerosis.