Canavan disease is a gene-linked neurological disorder that results in brain tissue degeneration.
The cause of the disease is a genetic disorder that causes oligodendrocytes to remain immature and then die, thereby not completing the synthesis of myelin sheaths. The mutation is in the gene that synthesizes an enzyme called aspartoacyclase.
Symptoms of Canavan disease usually appear during the first 3 to 6 months of life and, unfortunately, progress rapidly. Symptoms include lack of motor development, abnormal muscle tone, difficulty feeding, and an abnormally large head that has poor muscle control. Some children develop paralysis, blindness, and/or hearing loss. These children are usually not active and appear apathetic.
The prevalence of Canavan disease in the general population is unknown. Among people of Ashkenazi Jewish descent, the disease affects approximately 1 in 6,400 to 13,500 people, making 1 in every 40 to 58 Ashkenazi Jews a carrier.
Unfortunately, there is no cure or standard treatment for this disease. Treatment is symptomatic and supportive. Death usually occurs before age 10 although few children may survive into the teens and early 20s. The prognosis is poor.
Research is ongoing. The gene for the disease has been located and there are animal models for this disease. Gene transfer to the brain, metabolic therapy to provide a missing metabolite (acetate), and enzyme therapy have yielded some encouraging results.
Most people with Canavan disease die in childhood, although some survive into their teens or early twenties. In childhood they become severely mentally disabled and lose muscle control.
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