Canavan disease is rare genetic neurological disorder characterized by the spongy degeneration of the white matter in the brain. Canavan affects at birth. The affected newborns may look normal at birth, but they usually develop symptoms between 3-6 months of age.

The symptoms of Canavan disease include an abnormally large head (macrocephaly), lack of head control, severely diminished muscle tone resulting in "floppiness," and delays in reaching developmental milestones such as independent sitting and walking.

Most affected children develop life-threatening complications by 10 years of age. The cause of the rare disorder includes mutations in the aspartoacylase (ASPA) gene that affects the breakdown (metabolism) of the N-acetylaspartic acid (NNA). It is inherited as an autosomal recessive condition.

Canavan disease affects men and women equally. The disorder affects all ethnic groups, but happens with greater frequency in individuals of Ashkenazi Jewish descent.

The carrier frequency in Ashkenazi Jewish is estimated to be as high as one in 40-58 people. The risk for an affected child born to Ashkenazi Jewish parents is between 1 in 6,400 and 1 in 13,456. The overall incidence of Canavan disease in the general population is unknown.

A diagnosis of Canavan disease may be suspected in infants with the characteristic findings of the disorder. A diagnosis may be confirmed by a thorough clinical evaluation, a detailed patient history, and a variety of specialized tests.

These tests may include gas chromatography-mass spectrometry, a device that can detect elevated levels of NAA in the urine. Elevated levels of NAA can also be detected in the blood and cerebrospinal fluid (CSF).