Canavan Disease (CD)

van Bogaert-Bertrand Disease

Inheritance:

Autosomal recessive

Inheritance from both parents will result in the disease

Age range at onset:

Mild form: Childhood. Severe form: Neonatal or Infancy

Specialists you may see:

Symptoms

The most common form of Canavan disease is the severe infantile form. Affected people are usually normal at birth. Development problems become noticeable at around 3-5months, as infants do not develop motor skills such as the ability to turn over, sit without support or control head movements. They may also have symptoms such as hypotonia (reduced muscle tone) and a large head (macrocephaly). Infants with Canavan disease may have difficulties in feeding and swallowing, poor vision, disturbed sleep, irritability and seizures. Most with the severe form of Canavan disease do not survive into adolescence.

Mild/juvenile Canavan disease causes mild developmental delay, including delay to speech and motor skills. These may be so mild that they are never identified as Canavan disease, and may not have an effect on life expectancy.

Cause

Mutations in the ASPA gene cause Canavan Disease. This gene is used to make an enzyme which breaks down a compound called NAA in the brain. Without the ability to break it down, levels of NAA rise in those with Canavan Disease, creating a chemical imbalance leading to the symptoms described, although the role of NAA and how this causes these symptoms are not well understood. In the milder form of Canavan Disease, the enzyme’s activity is not so impaired, so NAA does not accumulate to such high levels.

Canavan Disease is most common in people with Ashkenazi Jewish ancestry.