This is a recently described hereditary neurological disorder. It is a progressive condition usually detectable in early childhood.
Newborns are floppy (hypotonic) at birth and motor and mental delays become evident within a few months. Developmental milestones may be severely delayed and some individuals never walk. The lower limbs are often stiff (spasticity). Speech is delayed and often slurred. Hearing loss may be present. The electroencephalogram (EEG) confirms the presence of seizures in some patients. Brain imaging reveals abnormal development of the brain. Some patients have skeletal deformities such as kyphoscoliosis (abnormal curvature of the spine) and foot deformities.
The eyes are deeply-set and strabismus (misalignment of the eyes) is often present. No information on the level of vision is available. The retina is malformed and many patients are near sighted.
This condition is inherited in an autosomal recessive pattern which requires that both members of a gene pair carry a mutation. The parents, with only a single mutation, are clinically normal but each of their children has a 25% risk of receiving both mutated copies (one from each parent) thereby inheriting the condition.
There are no specific signs at birth that enable clinicians to make the diagnosis. However, within a few months when the developmental delays become evident, the global nature of the condition is apparent. Pediatricians, pediatric neurologists, and other specialists are likely to collaborate on categorization of this disorder but genetic studies are required to determine the true diagnosis.
Some individuals may live to become adults but they often require intensive attention and care. No treatment has been reported but patients may benefit from physical therapy and assistive devices such as hearing aids, visual aids, and wheelchairs.