Deafness-dystonia-optic neuronopathy syndrome (DDON) is also known as Mohr-Tranebjaerg Syndrome. It is a genetic disease that includes hearing and vision impairment as well as neurological and psychiatric symptoms.
Males with DDON have hearing impairment in early childhood, usually beginning around 18 month of age. Symptoms include slowly progressive dystonia or ataxia in the teens, slowly progressive decreased vision beginning about age 20 years, and dementia beginning about age 40 years. Psychiatric symptoms such as personality change and paranoia may appear in childhood and progress. The hearing impairment appears to be constant in age of onset and progression, whereas the neurologic, visual, and neuropsychiatric signs vary in degree of severity and rate of progression. Females may have mild hearing impairment and focal dystonia.
Treatment is multifaceted and includes correcting, as much as possible, the hearing and vision symptoms, reducing dystonia and ataxia symptoms, and addressing psychiatric conditions.