How is Canavan disease inherited?
Canavan disease is inherited in an autosomal recessive manner. We all have two copies of most of our genes. We get one copy from our mother and another copy from our father. In Canavan disease, a person inherits two copies of the ASPA gene that is not working correctly. This causes the disorder. The parents have one working copy of the gene and one nonworking copy; they are carriers for Canavan disease. Carriers do not show symptoms of the condition themselves. Each time two carriers have a child, there is a 25% chance they will have a child with Canavan disease. There is a 50% chance they will have a child who is a carrier, but does not have Canavan disease. There is a 25% chance they will have a child who neither has Canavan disease nor is a carrier for the disorder.