Clinician-Driven Reanalysis of Exome Sequencing Data From Patients With Inherited Retinal Diseases

Keep an Eye on Next Generation Sequencing (NGS) Technology: Secondary Findings and Differential Diagnosis in Inherited Retinal Dystrophies (IRDs)

Background: Next Generation Sequencing (NGS) Technology has represented a revolution in the molecular characterization of Inherited Retinal Dystrophies (IRDs), which are among the most genetically and phenotypically heterogeneous conditions. NGS has allowed the characterization of a consistent number of patients affected by IRDs, but at the same time, unexpected results can pose diagnostic dilemmas. Aim: The purpose of this review is to describe possible scenarios as a reference for ophthalmologists and geneticists who are involved in this particularly complex field. Methods: A review of the existing literature has been performed. In addition, examples have been brought, from a series of patients that have been analyzed at the University of Naples "Federico II"-CEINGE Biotecnologie Avanzate "Franco Salvatore". Results: Unexpected results in the genetic characterization of IRDs are not uncommon. The main findings are additional variants that potentially modify phenotypes, deletions masked by apparent homozygosity, and pathogenic variants leading to phenotypes revisitation. Conclusions: The high genetic and phenotypic heterogeneity characterizing IRDs have been greatly advantaged by the advent of NGS Technology. At the same time, the not uncommon finding of unexpected data poses diagnostic criticisms that need to be addressed. In this review, we describe possible scenarios, and we go through some more complex genotype-phenotype correlations.

A case of massive hematoma: reflections on hypermobile Ehlers-Danlos syndrome

Ehlers-Danlos Syndrome (EDS) refers to a group of connective tissue disorders characterized by significant clinical and genetic variability, affecting multiple systems in the body. Classified as a rare disease, EDS includes 14 subtypes, all marked by joint hypermobility, skin extensibility, and tissue fragility. These subtypes present with a wide range of clinical manifestations and severities, including frequent joint dislocations, scoliosis, arterial dissections, and organ ruptures. Hypermobile EDS (hEDS) is the most common subtype, with newly established clinical diagnostic guidelines. In this case, a patient presented with minor hemoptysis over 8 h, and a chest CT scan revealed a massive hematoma in the left lower lung. Due to the complexity and varied presentations of EDS, misdiagnosis is common. This report shares our experience with diagnosis and treatment in this case, highlighting the importance of increasing awareness for improved survival outcomes.

GREGoR: Accelerating Genomics for Rare Diseases

Rare diseases are collectively common, affecting approximately one in twenty individuals worldwide. In recent years, rapid progress has been made in rare disease diagnostics due to advances in DNA sequencing, development of new computational and experimental approaches to prioritize genes and genetic variants, and increased global exchange of clinical and genetic data. However, more than half of individuals suspected to have a rare disease lack a genetic diagnosis. The Genomics Research to Elucidate the Genetics of Rare Diseases (GREGoR) Consortium was initiated to study thousands of challenging rare disease cases and families and apply, standardize, and evaluate emerging genomics technologies and analytics to accelerate their adoption in clinical practice. Further, all data generated, currently representing ~7500 individuals from ~3000 families, is rapidly made available to researchers worldwide via the Genomic Data Science Analysis, Visualization, and Informatics Lab-space (AnVIL) to catalyze global efforts to develop approaches for genetic diagnoses in rare diseases (https://gregorconsortium.org/data). The majority of these families have undergone prior clinical genetic testing but remained unsolved, with most being exome-negative. Here, we describe the collaborative research framework, datasets, and discoveries comprising GREGoR that will provide foundational resources and substrates for the future of rare disease genomics.