In genetically susceptible individuals, prolonged hyperglycaemia leads to chronic metabolic and haemodynamic changes [8,9] whose effects, including those driven by transforming growth factor beta 1 (TGFβ1), promote structural abnormalities in the kidney such as glomerular basement membrane thickening, podocyte injury, and mesangial matrix expansion, with the later development of irreversible glomerular sclerosis and tubulointerstitial fibrosis [10]. The gene discussed is TGFB1; the disease is glomerulosclerosis.