NORRIE DISEASE IN A FAMILY WITH A MANIFESTING FEMALE CARRIER

Objectives: To show that Norrie disease can occur in a girl and to des cribe her ophthalmologic and genetic features. Methods: Amplification of DNA polymerase chain reaction and sequencing of asymmetric polymera se chain reaction for exon 3 were performed on the blood specimen obta ined from a girl born with bilateral retinal detachments. Patient: A f emale child with bilateral retinal detachment who had 2 uncles in whom Norrie disease had already been diagnosed. Results: The child had a m utation in the third exon (T776-->A; Ile 123-->Asn) identical to the m utation found in her uncles. Conclusions: Norrie disease can occur in girls. The most likely explanation is nonrandom or unfavorable X inact ivation, although timing of development of the peripheral retina and i ts blood supply could render it vulnerable to effects of the mutant al lele at a critical developmental phase.