Blepharoptosis, Myopia, Ectopia Lentis
Patient Information
Characteristics
Background and History
This unique combination of eye findings has been reported in a mother and two daughters. Ectopia lentis (dislocated lenses of the eye) and nearsightedness are common features among hereditary disorders.
Lens dislocations have been recognized since the middle of the eighteenth century and the term ‘ectopia lentis’ was coined in 1856.
Clinical Correlations
The eyelids drooped mildly (blepharoptosis) but moved normally on upward gaze. The eyeballs were abnormally large in the mother and one daughter [a cause for myopia (nearsighted)] while the nearsightedness in the other daughter in which the eyes were normal-sized was due to the displacement of the lens (ectopia lentis). The lid creases in the upper eyelids were abnormally high indicating the muscle lifting the lid was attached abnormally. The eyes moved normally. Vision was near normal in this family once the nearsightedness was corrected with lenses.
No systemic abnormalities were found.
Genetics
Inheritance
The presence of similar findings in a parent and two offspring suggest autosomal dominant inheritance but no mutation has been identified.
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
Diagnosis and Prognosis
An ophthalmologist would be the most likely to diagnose this disorder. The nearsightedness can be corrected with lenses and the dislocated lenses can be removed surgically. Lifespan is apparently normal.
Web Resources
Printer Friendly Version: Ctrl/Cmd+P