This is one of many disorders in which abnormalities of the retina (light sensing tissue in the eye) are associated with malformations or abnormalities in the rest of the body.
Infants seem to be normal at birth but there are soon obvious signs of developmental delays. Patient milestones of sitting and walking occur late. This is complicated within a few years by loss of vision to the level of light perception only. The face appears somewhat ‘coarse’ with a depressed nasal bridge and a prominent nose. Diabetes mellitus is caused by insulin resistance and therefore circulating levels of insulin are often elevated. In males the testes are small and they may develop gynecomastia (breasts). Menstruation is abnormal in females. An ususual pattern of pigmentation can be seen under the arms, behind the knees, and at the nape of the neck. All patients reported so far have been mentally retarded and deaf.
The retina has abnormal pigment clumping in a pattern resembling that seen in a relatively common eye disease known as retinitis pigmentosa. The optic nerves which carry visual signals to the brain are also damaged. Cataracts and nystagmus (dancing of the eyes) are often seen as well.
Nothing is known about the genetic basis for this condition. However, family patterns of the disease suggest that this is an autosomal recessive disorder in which two copies of a mutated gene are necessary. By extension, parents of such children could expect that there is a 25% risk that subsequent children would inherit the condition.
A team is required for the diagnosis of this disorder. The first signs of developmental delays might be evident to a pediatrician when children first learn to sit, walk, and stand. An ophthalmologist could diagnose the eye disease and might suggest surgery to remove cataracts if they are visually significant. An ear, nose, and throat specialist should evaluate the hearing problem for the presence of other disease. An endocrinologist should evaluate the diabetic disease and sex hormones. No other treatment is known and there is no information on longevity.