Sporadic, some Autosomal dominant cases noted
Typically not genetic, some examples of inheritance from both parents
Age range at onset:
From early childhood to adulthood
Specialists you may see:
Alexander disease usually presents between the age of 4 and 10 years but may present in the teens or adulthood. Symptoms include: speech difficulties and swallowing abnormalities, spasms of the soft palate (palatal myoclonus), poor coordination and walking difficulties. Other problems include sleep disorders and urinary difficulties.
Progression is slow but eventually leads to respiratory insufficiency. Those with Alexander Disease type 2 may survive for around 25 years post-diagnosis or longer in the adult form.
A mutation in the GFAP (Glial Fibrillary Acidic Protein) gene is the cause of Alexander Disease. Normally GFAP is important for supporting the myelin (white matter) that surrounds the nerve fibres in the brain. In Alexander Disease there is an overproduction of abnormal GFAP which results in damage of normal myelin formation and maintenance and impairment of brain function.
In most people with Alexander Disease the mutation in the GFAP gene occurs at the time of conception (this is called de novo) and is not inherited from a parent. However occasionally Type 2 Alexander Disease is caused by a GFAP mutation that has been inherited from one of the parents
News, research and treatment
ULF suggest a third type of Alexander Disease, a juvenile form of intermediate severity on a spectrum between type 1 and type 2