Abstract: Purpose: To describe with multimodal imaging including the use of ultra-widefield optical coherence tomography imaging a distinct phenotype of autosomal recessive nanophthalmos associated with a novel mutation of the MFRP gene (membrane-type frizzled-related protein).
Methods: Case report of a single patient followed by the Weill Cornell Medicine Department of Ophthalmology Retina and Glaucoma Services, and review of the relevant literature.
Results: A patient with a novel homozygous mutation in the MFRP gene (c.472C>T) presented with nanophthalmos, optic disk drusen, foveal hypoplasia, and extensive peripheral retinoschisis, which was revealed to be multilevel retinoschisis on ultra-widefield optical coherence tomography. Unlike other reported cases, the findings associated with this novel mutation did not include foveoschisis or clinically obvious retinitis pigmentosa. The patient underwent prophylactic peripheral laser iridotomy in both eyes.
Conclusion: Here, we present a patient with nanophthalmos, optic disk drusen, and foveal hypoplasia associated with extensive peripheral retinoschisis imaged by ultra-widefield optical coherence tomography, but not foveal retinoschisis or prominent retinitis pigmentosa. The findings may expand the clinical spectrum of MFRP -associated nanophthalmos.
References: Sundin OH, Dharmaraj S, Bhutto IA, et al. Developmental basis of nanophthalmos: MFRP is required for both postnatal ocular growth and postnatal emmetropization. Ophthalmic Genet 2008;19:1–9.
Othman MI, Sullivan SA, Skuta GL, et al. Autosomal dominant nanophthalmos (NNO1) with high hyperopia and angle-closure glaucoma maps to chromosome 11. Am J Hum Genet 1998;63:1411–1418.
Sundin OH, Leppert GS, Silva ED, et al. Extreme hyperopia is the result of null mutations in MFRP, which encodes a frizzled-related protein. Proc Natl Acad Sci U S A 2005;102:9553–9558.
Crespí J, Buil JA, Bassaganyas F, et al. A novel mutation confirms MFRP as the gene causing the syndrome of nanophthalmos-renititis pigmentosa-foveoschisis-optic disk drusen. Am J Ophthalmol 2008;146:323–328.
Wasmann RA, Wassink-Ruiter JS, Sundin OH, et al. Novel membrane frizzled-related protein gene mutation as cause of posterior microphthalmia resulting in high hyperopia with macular folds. Acta Ophthalmol 2014;92:276–281.
Won J, Smith RS, Peachey NS, et al. Membrane frizzled-related protein is necessary for the normal development and maintenance of photoreceptor outer segments. Vis Neurosci 2008;25:563–574.
Karczewski KJ, Francioli LC, Tiao G, et al. The mutational constraint spectrum quantified from variation in 141,456 humans. Nature 2020;581:434–443.
Neri A, Leaci R, Zenteno JC, et al. Membrane frizzled-related protein gene-related ophthalmological syndrome: 30-month follow-up of a sporadic case and review of genotype-phenotype correlation in the literature. Mol Vis 2012;18:2623–2632.
Mukhopadhyay R, Sergouniotis PI, Mackay DS, et al. A detailed phenotypic assessment of individuals affected by MFRP-related oculopathy. Mol Vis 2010;16:540–548.
Dinculescu A, Estreicher J, Zenteno JC, et al. Gene therapy for retinitis pigmentosa caused by MFRP mutations: human phenotype and preliminary proof of concept. Hum Gene Ther 2012;23:367–376.
No Comments.