Since that time, much has been learned about the genetic and biochemical bases of the disease. Recent developments in the understanding of the genetic defect involved in Canavan Disease have increased not only the ability to diagnose CD accurately, but also the accuracy of carrier screening and prenatal detection for at-risk families. One of the earliest signs of CD recognized by many parents is overall low muscle tone and lack of head control. As the child grows, motor skills and mental functioning deteriorate. The child eventually becomes blind, but hearing remains sharp.
Affected children continue to recognize and respond to the voices of their primary caregivers.
Difficulties which arise as the child grows include stiffness, weakness of the muscles, seizures, and feeding problems. I t is not possible to describe all children with CD in the same way, since the presentation and progression of illness varies from child to child. Although many children with CD die in infancy, some survive into adolescence and even occasionally into adulthood. One of the earliest signs of Canavan Disease recognized by many parents is overall low muscle tone and lack of head control. C anavan Disease belongs to a group of conditions known as leukodystrophies, which result from defects in myelin.