A cataract is an opacification of the lens in the eye. This is one of numerous inherited congenital cataract conditions but specifically associated with learning and movement problems.
A consanguineous Tunisian family with three affected children has been reported with this disorder. The opacification is of a specific type in which the opacification occurs in the posterior portion of both lenses. It is presumably present at birth and vision is good following surgical removal of the lenses.
Developmental milestones are delayed. Children do not walk until about 2 years of age and speech begins at about 5 years. They may have some learning difficulties as well. The parents are normal.
This condition follows an autosomal recessive inheritance pattern in which both copies of a gene are mutated. The parents are carriers, i.e., they carry a single copy of a gene mutation and do not have cataracts but each of their children have a 25% chance of inheriting the mutation from each of their parents and therefore to have this disorder.
The diagnosis can be made by an ophthalmologist, probably at birth. The developmental delay may not be evident until several years of age and might be detected by a pediatrician or a neurologist.
The cataracts can be surgically removed with restoration of eyesight. Special education might enable better adaptation and learning. There is no evidence of an impact on longevity or of other physical disabilities. Studies of the brain have been normal.