Ocular phenotypes associated with two mutations (R121W, C126X) in the Norrie disease gene.

PURPOSE

To describe the ocular phenotypes associated with 2 mutations in the Norrie disease gene including a manifesting carrier.

METHODS

Ophthalmological examinations were performed in 2 affected males and one manifesting carrier. Genomic DNA was analyzed by direct sequencing of the Norrie disease gene.

RESULTS

Family I: A 29-year-old male had the right eye enucleated at the age of 3 years. His left eye showed severe temporal dragging of the retina and central scars. Visual acuity was 20/300. DNA analysis revealed a C-to-T transition of the first nucleotide in codon 121 predicting the replacement of arginine-121 by tryptophan (R121W). Both the mother and maternal grandmother carry the same mutation in heterozygous form. Family 2: A 3-month-old boy presented with severe temporal dragging of the retina on both eyes and subsequently developed retinal detachment. Visual acuity was limited to light perception. His mother's left eye was amaurotic and phthitic. Her right eye showed severe retinal dragging, visual acuity was reduced to 20/60. DNA analysis revealed a T-to-A transversion of the third nucleotide in codon 126 creating a stop codon (C126X). The mother and maternal grandmother were carriers.

CONCLUSION

Mutations in the Norrie disease gene can lead to retinal malformations of variable severity both in hemizygous males and manifesting carriers.