Troyer syndrome is one of more than 40 genetically-distinct neurological disorders known collectively as the hereditary spastic paraplegias. These disorders are characterized by their paramount feature of progressive muscle weakness and spasticity in the legs. Additional symptoms of Troyer syndrome (also called SPG20) include leg contractures, difficulty walking, speech disorders, drooling, atrophy of the hand muscles, developmental delays, fluctuating emotions, and short stature. Onset is typically in early childhood, and symptoms gradually worsen over time. Troyer syndrome is an autosomal recessive disorder (meaning that both parents must carry and pass on the defective gene that produces the illness) that results from a mutation in the spastic paraplegia gene (SPGP20) located in chromosome 13 that results in loss of the spartin proteins. The disease was first observed in Amish families in Ohio. Diagnosis is made by specialized genetic testing.
There are no specific treatments to prevent or slow the progressive degeneration seen in Troyer syndrome. Symptomatic therapy includes antispasmodic drugs and physical therapy to improve muscle strength and maintain range of motion in the legs. Assistive devices may be needed to help with walking.
Prognosis varies, although the disease is progressive. Some patients may have a mild form of the disease while others eventually lose the ability to walk normally. Troyer syndrome does not shorten the normal life span.
The NINDS supports research on genetic disorders such as the hereditary spastic paraplegias. A gene for Troyer syndrome has been identified and others may be identified in the future. Understanding how these genes cause Troyer syndrome and the hereditary spastic paraplegias in general will lead to ways to prevent, treat, and cure these disorders.