Cataracts, Congenital, with Cleft Palate
Defective Genes
Clinical Characteristics
Ocular Features
Bilateral congenital cataracts are usually present together with upward-slanting and narrowed lid fissures. The upper eyelids appear abnormally thick and epicanthus is common. Nothing is known about the location or morphology of the lens opacities.
Systemic Features
Anomalies of the palate consisting of clefting, bifid uvula, and sub-mucous clefts are consistently present. Oral anomalies such as thickening of the lower lid and small mouth are commonly seen. The nose may be both long and broad. The face usually appears oval and the forehead is prominent. A cartilaginous nodule often appears on the helix of low-set and anteriorly rotated ears. The fingers may be long and thin.
No cardiac or neurologic defects have been reported.
Genetics
Inheritance
Based on the transmission pattern in the single 4 generation family reported, autosomal dominant inheritance is likely. Array comparative genomic hybridization revealed an interstitial amplification at Xp21.1 but this did not segregate precisely with the clinical pattern and is possibly a copy number polymorphism. Both sexes are about equally affected.
Pedigree
Autosomal dominant
Autosomal dominant disorders require only one mutation for the disease to be expressed. Since an affected parent has two chromosomes, only one of which has the mutant gene, parents can expect that half (50%) of their children will receive that one and inherit the disease. It is common for individuals that inherit the mutation, however, to not have evidence of the disease (nonpenetrance).
Autosomal dominant inheritance leads to a vertical pattern of transmission