Whole exome sequencing and whole genome sequencing in undiagnosed disease: of value for certain patient populations

Whole exome sequencing and whole genome sequencing in undiagnosed disease: of value for certain patient populations Whole exome sequencing and whole genome sequencing (WES/WGS) as a diagnostic tool has become more readily available. A recent study on the diagnostic yield in a highly selected patient population with undiagnosed disease has demonstrated the power of a stringent diagnostic process that includes WES/WGS. Up to one third of patients received a diagnosis, following critical clinical review of tests performed previously, additional targeted biochemical or genetic diagnostic tests and/or the application of WES/WGS. In more than 60% of the resolved cases, WES or WGS played a crucial role. The success of the Undiagnosed Disease Network relies strongly on patient selection, review of clinical symptoms and medical records by a team of specialists, and close collaboration with basic scientists and laboratories to study the clinical impact of possible genetic variations and mutations that are discovered through WES/WGS. Although the results are impressive, it remains to be determined whether such a dedicated approach is feasible in a non-research setting.