Canavan Disease

Canavan disease is an autosomal recessive inherited disorder that affects aspartic acid metabolism and causes progressive degeneration of the white matter of the brain formed by the myelinated axons of a large number of neurons.

This neurodegenerative disease is caused by mutations in the ASPA gene that codes for aspartoacylase, an enzyme with a fundamental role in nervous tissue.

The incidence of the pathology in the general population is estimated to be between 1 in 200,000 and 1 in 400,000 individuals. It increases markedly in Askenazi Jews in whom there is 1 case in 5,000 to 6,700 individuals.

Symptoms of Canavan disease vary, but usually manifest between three and five months of age and include hypotonia (low muscle tone), rapid increase in head circumference (macrocephaly), lack of head control and developmental delay. These are children who cannot crawl, walk, sit or talk. Eventually they may have seizures, and have feeding problems. They present leukodystrophy and elevated levels of N-acetylaspartic acid in urine.

There is a mild form of Canavan disease (juvenile type) in which children have normal or slightly delayed motor and speech development, without regression, usually requiring only speech therapy to improve their communication skills.

There is currently no cure for Canavan disease. In young children with Canavan disease, treatments are aimed at facilitating nutrition and hydration, avoiding infections, physiotherapy to minimize the risk of contractures and developing motor skills.