The Current Benefit of Genome Sequencing Compared to Exome Sequencing in Patients with Developmental or Epileptic Encephalopathies

Overview

Journal Mol Genet Genomic Med

Specialty Genetics

Date 2023 Feb 14

PMID 36785910

Authors

Anna Grether

Ivan Ivanovski

Martina Russo

Anais Begemann

Katharina Steindl

Lucia Abela

Michael Papik

Markus Zweier

Beatrice Oneda

Pascal Joset

Anita Rauch

Affiliations

Soon will be listed here.

Abstract

Background: As the technology of next generation sequencing rapidly develops and costs are constantly reduced, the clinical availability of whole genome sequencing (WGS) increases. Thereby, it remains unclear what exact advantage WGS offers in comparison to whole exome sequencing (WES) for the diagnosis of genetic diseases using current technologies.

Methods: Trio-WGS was conducted for 20 patients with developmental or epileptic encephalopathies who remained undiagnosed after WES and chromosomal microarray analysis.

Results: A diagnosis was reached for four patients (20%). However, retrospectively all pathogenic variants could have been detected in a WES analysis conducted with today's methods and knowledge.

Conclusion: The additional diagnostic yield of WGS versus WES is currently largely explained by new scientific insights and the general technological progress. Nevertheless, it is noteworthy that whole genome sequencing has greater potential for the analysis of small copy number and copy number neutral variants not seen with WES as well as variants in noncoding regions, especially as potentially more knowledge of the function of noncoding regions arises. We, therefore, conclude that even though today the added value of WGS versus WES seems to be limited, it may increase substantially in the future.

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