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VARIABLE EXPRESSION OF RETINOPATHY IN A PEDIGREE OF PATIENTS WITH INCONTINENTIA PIGMENTI
Connie J Chen1, Ian C Han, Morton F Goldberg
1Wilmer Eye Institute, Johns Hopkins Hospital, Baltimore, Maryland.
Purpose:
To characterize the varied ocular manifestations of incontinentia pigmenti (IP) in a large pedigree.
Methods:
All available members of the kindred who were affected with IP were examined with ophthalmoscopy, wide-field color photos, and fluorescein angiography.
Results:
Individual family members demonstrated variable expression of retinopathy characteristic of IP. There was severe retinopathy in two eyes: one associated with concurrent persistent fetal vasculature and another with rhegmatogenous retinal detachment. Another individual with biopsy-confirmed IP demonstrated no retinopathy in either eye. When present, retinopathy manifested asymmetrically between eyes of the same individual.
Conclusion:
Cutaneous manifestations of IP are irregular and nonuniform due to lyonization of the X chromosome. In this report, we identify asymmetric retinal disease between eyes in the same individual and variable retinal findings within the kindred. These differences may be explained by random inactivation of the X chromosome or other epigenetic modifications.
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