This recently described condition is characterized by skeletal abnormalities and a malfunction of the retina in the eye resulting in short stature and visual difficulties among other features.
Visual difficulties such as excessive sensitivity to light and poor vision may be noted during adolescence. Some patients have nystagmus (jerky movements of the eyes). Functional tests of the retina (the tissue in the back of the eye that responds to light) such as the electroretinogram (ERG) reveal decreased responsiveness of the rods and cones. The pigmentation of the retina is abnormal and the optic nerve is usually pale.
There are developmental deformities in the ribs, spinal vertebrae, and proximal bones of the limbs. The result is delayed growth and eventual short stature. The arms and legs appear shortened and the chest is bell-shaped and flat. Mental development and function are normal. The forehead is often prominent.
This is an autosomal recessive disorder in which mutations in a specific pair of genes are responsible. The parents are physically normal, carrying the mutation on one member of the pair. However, there is a 25% risk in each child of such parents to inherit both mutations.
The diagnosis is likely made by a multidisciplinary team of specialists including pediatricians, neurologists, ophthalmologists, and orthopedists. There is no effective treatment for the overall disorder.
Nothing is known regarding longevity. Low vision aids may be helpful, especially in school-age children.