Whole Exome Sequencing for Romanian Patients With Neurodevelopmental Disorders Through an International Collaboration

Neurodevelopmental disorders (NDDs) are a highly diverse group of conditions that manifest through motor, cognitive, and behavioral impairments, representing the most common chronic condition encountered in children. As these often have a genetic cause or component, extensive genetic testing, particularly whole exome sequencing (WES), plays a critical role in their diagnosis, management, and prevention. Here, we present detailed clinical and genetic data on 54 Romanian patients included in the NeuroMyoDredger project, and provide an overview of the current landscape of genetic testing availability for NDDs in Romania, commenting on current barriers and the importance of integrating advanced genomic technologies into national healthcare strategies. A total of 54 undiagnosed Romanian patients with an initial clinical suspicion of unspecific NDD have benefited from singleton WES (including CNV and mitochondrial DNA analysis), with a diagnostic yield of 50%. Furthermore, a substantial proportion of cases (eight patients, 14.81%) yielded nondefinitive results involving variants of uncertain significance, with potential pathogenic relevance. Our findings align with the existing literature data, supporting the integration of singleton WES with CNV and mitochondrial variants detection as a first-line investigation in the diagnostic workflow for NDDs.