This is one of a large group of hereditary disorders resulting in impaired mobility and often more widespread disabilities involving touch and locomotion. These conditions result from mutations (changes) in specific genes.
The onset of symptoms occurs at any time from childhood to adult life. Walking may be delayed and is often accompanied by clumsiness and frequent falls. Stiffness in the limbs, especially the legs, along with muscle weakness at some point eventually occurs. This disorder is progressive and many individuals lose their ability to walk independently after 2-3 decades. Speech is often slurred, and swallowing becomes impaired while bladder and bowel control is often impacted as well. Some loss of touch sensation may be present.
No measurement of vision has been reported but eye movements such as following visual targets are sometimes abnormal. Rare patients have been reported to have cataracts.
DNA mutations in both members of a specific gene are responsible for this condition. The transmission pattern is autosomal recessive. Individuals with a single mutation in one of the pair are clinically normal but when both mother and father carry the single mutation they confer a 25% risk in each of their children to inherit this disorder.
No evidence of this condition is present at birth but signs of gait difficulties follow the onset of walking. Pediatricians and neurologists are likely to collaborate in the diagnosis and care of affected individuals.
No treatment for the general condition is available. Physical therapy may be helpful but the progression of neurologic impairment is relentless. Nothing is known regarding longevity.