RPE65 Variation RPE65 pG140E, c419G>A, First case presentation

Abstract

We are reporting a new variation RPE65 pG140E, c419G>A. An asymptomatic male with fine bright white dotes in macula and generalized constricted visual fields. Introduction The RPE65 protein is the source of isomerohrydrolase activity (conversion of all-trans retinyl ester to 11-cis retinol) in the retinal pigment epithelium [1]. The characterization of RPE65 gene was first described by Nicoletti et al. 1995 [2], which encodes the abundant 61-kD protein in Retinal Pigment Epithelium (RPE) monolayer simple epithelium opposed to the outer surface of the retina photoreceptor cells. RPE works in metabolism in outer layers that are essential to continued maintenance of the photoreceptor cells, including vision functionality as visual cycle photoreceptor recycling and outer segment phagocitosis [3]. The gene is maps to human chromosome 1p31. Among functions are 1) Phagocytizes periodically the tips of outer segments, process whose defects leads to retinal degeneration, 2) RPE65 is site of many enzymes involved in retinoid metabolism, including retinyl ester synthetase and 3) Lecithin: retinol acyltranferase, 4) Retinyl ester hydrolase, 5) Retinol isomerase, 6) 11-cis retinol deshidrogenase as well as 7) Rpe-/retina-specific cellular retinaldehyde binding protein, 8) ion transport 9) digestion of phagosomes and 10) detoxification of photoreceptors by products. Autosomal recessive childhood-onset severe retinal dystrophy (arCSRD) designates a heterogenous group of disorders affecting rod and cone photoreceptors simultaneously [4]. Disease genes implicated in other forms of arCSRD are expected to encode proteins presents in the neuroretina, it is in intimate contact with the outer segments of rods and cones via the microvillus surrounding the photoreceptos. The first family described with RPE65 mutation was in 1963 was by Waardenburg all normal children from two affected parents were reported [5]. Chung and Talboulsi in 2009 described another family with moderate impairment at infancy that progresses to total blindness by mild to late adulthood [6]. Morimura in 1998 summarized the clinical criteria distinguishing retinitis pigmentosa (RP) from LCA, however variability is among them [7]. We are reporting a new variation RPE65 pG140E, c419G>A (new variation, not previously reported from father) and p. I98HfsX26, c.292_311del20 (known pathogenic variationfrom mother) in a 3 years old. Methodology We examined a 3 years old that starts bumping into objects since 1 year old. Mother noticed he likes to stared at sun. He is scared at walking and eating and mother alleged he looks not secure. During ocular examination he presented with Central Steady and Maintains vision OU, no Nystagmus. Fundus examination is about normal, central choroidal shown no thickenings of vessels, there are scarce fine dots all over the macula (Figure 1), the diagnosis is inherited retina dystrophy OU. We then perform ocular full examination to parents and sibling and we establish a more likely pattern of autosomal recessive dystrophy. Fundus picture examination, auto fluorescence, ocular coherence tomography were taken of each member of the family. After consent was taken, blood samples drain were taken and send for molecular DNA was submitted to GeneDx. The specimen was enriched for the complete coding region and splice site junctions for most genes of the human genome using a propietary capture system developed by GeneDx for next-generation sequencing with CNV calling (NGS-CNV). The enriched targets were simultaneously sequenced with paired-end reads on an Ilumina platform. We describe a new variation of the RPE65, p.G140E, c.419G>A Villanueva A* Retina Genomics Institute, Canada and Mexico *Address for Correspondence Villanueva A, Retina Genomics Institute, Canada and Mexico, Tel: 9992233623; E-mail: dr.villanueva@mejoravisionmd.com Submission: February 19, 2019 Accepted: March 21, 2019 Published: March 25, 2019 Copyright: © 2019 Marzulli M, et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Case Presentation Open Access Journal of Gene Therapy