Several gene polymorphisms have been described that may affect the rate of renal failure progression and/or the individual susceptibility to ACE inhibition. These polymorphisms include genes encoding for key proteins of the renin-angiotensin system and extracellular matrix turnover. In addition, we will screen for novel polymorphisms in genes determining structural proteins of the glomerular filter, and search for gene mutations causing renal hypo-/dysplasia. Objective 3 is to evaluate whether any of these mutations predict spontaneous disease progression and the therapeutic response to ACE inhibition and intensified blood pressure control.