Photo Credit: JOSE LUIS CALVO MARTIN & JOSE ENRIQUE GARCIA-MAURIÑO MUZQUIZ
Patients with c.5237 G > A: p.Arg1746Gln variants in CDH23 may present with mild disease phenotypes, including sector retinitis pigmentosa (RP), according to results published in Ophthalmic Genetics. Michel Michaelides, MD, and colleagues aimed to determine the genotypes and phenotypes of patients with mild RP, including sector RP with two pathogenic variants in CDH23. The researchers assessed medical history, comprehensive ophthalmologic examination, multimodal retinal imaging, and genetics. Three unrelated cases presented with variable clinical phenotypes for Usher syndrome type 1 and were found to have two pathogenic variants in CDH23, with the mis-sense variant c.5237 G more than A: p.Arg1746Gln present in all cases. Cases one and three had mild RP with mid peripheral and posterior pole sparing, while case two had sector RP. Full-field electroretinography results “were consistent with the marked loss of retinal function in both eyes” in cases one and two. Dr. Michaelides and colleagues wrote that the results can be used to improve genetic counselling and disease prognostication.