Autosomal dominant polycystic kidney disease is one of the most common hereditary disorders, being 10 times more common than sickle cell disease, 15 times more common than cystic fibrosis, and 20 times more common than Huntington's disease. In addition, the disease accounts for 8 to 10 percent of the cases of end-stage renal disease, for which medical care costs exceed $200 million a year. The name previously given to the disorder, “adult polycystic kidney disease,” belies its true scope by focusing on the kidney and by confining the disorder to adults. In fact, autosomal dominant polycystic kidney disease is a . . .