As the proportion of the genome accessible for clinical interrogation increases from a handful of known disease-associated genes to encompass nearly all our 20,000 genes, the provision for genetic testing is changing rapidly. Are existing guidelines and standards of practice fit to meet the challenges - of scalability and accuracy of analysis and interpretation of the test and its results - presented by whole genome based testing?

The development of whole genome analysis (WGA) is reaching a tipping point in the UK as it moves from being a tool used only by researchers to a potentially powerful clinical diagnostic technique. Yet the lack of consensus on the optimal method for WGA, makes variations in approaches used to analyse genomic sequence data inevitable. This variation can result in disparities in outcome - i.e.the same genome, analysed by two different methods, may yield two different diagnostic conclusions. Whilst it is constructive to allow WGA providers flexibility in their choice of methods and approaches (in order to drive innovation and work towards optimal solutions), it is nonetheless incumbent upon the health system to work to minimise variations in practice, to ensure, as far as reasonably practicable, that patients receive the same quality of care (and outcomes) regardless of the methodology used to achieve their diagnosis.

Standards and best practice guidelines are an essential part of the quality assurance framework within NHS genetics services. Ensuring such standards are fit for purpose and universally adopted will be particularly important as the number of providers for genetic testing and analysis services in the UK increases.

Read more in Setting the right standards for clinical genome analysis