Case report of a PRDM5 linked brittle cornea syndrome type 2 in association with a novel SLC6A5 mutation

The application of high-throughput sequencing technology in corneal diseases

High-throughput sequencing technology, also known as next-generation sequencing technology, can explore new biomarkers and specific gene mutations. It has a pivotal role in promoting the gene research, which can limit the detection area, lessen the time needed for sequencing. Also, it can quickly screen out the suspected pathogenic genes of patients, gain the necessary genetic data, and provide the basis for clinical diagnosis and genetic counseling. In the research of corneal diseases, through the DNA sequencing of patients' diseased cells, it can provide a deeper understanding of corneal diseases and improve the diagnosis, classification and treatment alternatives of various corneal diseases. This article will introduce the application progress of high-throughput sequencing technology in corneal diseases, which will help to understand the application of this technology in various corneal diseases.

Homozygous Val6Gly Variation in PRDM5 Gene Causing Brittle Cornea Syndrome: A New Turkish Case

Introduction

Brittle cornea syndrome (BCS) is a rare connective tissue disorder with ocular and systemic features. Extreme corneal thinning and fragility are the main hallmarks of BCS.

Case Report

A 4-year-old boy presented with recurrent spontaneous corneal perforation. He had blue sclera, corneal leucoma, irregular iris, shallow anterior chamber, corneal astigmatism, and bilateral corneal thinning. He also had several systemic features including hearing loss, skin hyperelasticity, joint hypermobility, scoliosis, and umbilical hernia. A diagnosis of BCS was confirmed with molecular analysis. A homozygous c.17T>G, p.(Val6Gly) variation was identified in the PRDM5 gene.

Discussion

p.(Val6Gly) variation in PRDM5 was previously reported in 2 patients with BCS. We also considered PRDM5 c.17T>G, p.(Val6Gly) variation as pathogenic based on the following features: the absence of the variation in population databases, in silico predictions, segregation analysis, and clinical signs of our patient. Extremely thin and brittle corneas lead to corneal perforation spontaneously or after minor trauma. Nearly all patients have lost their vision because of corneal rupture and scars. The key challenge in the management of BCS is the prevention of ocular rupture which relies on early diagnosis. Early diagnosis allows for taking prompt measures to prevent ocular rupture.