Many patients, however, with both unilateral and bilateral RAS,tolerate ACE inhibitors.9 In fact, Chrysochou et al9 showed that reducing intraglomerular pressure with renin-angiotensin blockadehas a protective effect on renal function and a mortality benefit in these patients.10 This is thought to be through the same mechanism that ACE inhibitors delaythe progression of other forms of chronic kidney disease, that is, reducingproteinuria and the vascular protective effect on diseases that usually accompanyRAS like coronary artery disease. The gene discussed is REN; the disease is chronic kidney disease.