A paradigm shift in the delivery of services for diagnosis of inherited retinal disease
- James O'Sullivan1,2,
- Brendan G Mullaney1,
- Sanjeev S Bhaskar1,
- Jonathan E Dickerson1,2,
- Georgina Hall1,
- Anna O'Grady1,
- Andrew Webster3,4,
- Simon C Ramsden1,
- Graeme C Black1,2
- 1Genetic Medicine, Manchester Academic Health Sciences Centre, Central Manchester Foundation Trust, St Mary's Hospital, Manchester, UK
- 2Genetic Medicine, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, UK
- 3Institute of Ophthalmology, UCL, London, UK
- 4Moorfields Eye Hospital, London, UK
- Correspondence to Professor Graeme C Black, Genetic Medicine, Manchester Academic Health Sciences Centre, Central Manchester Foundation Trust, St Mary's Hospital, Manchester M13 9WL, UK;
- Received 22 February 2012
- Accepted 23 March 2012
Objectives Current technologies for delivering gene testing are labour-intensive and expensive. Over the last 3 years, new high-throughput DNA sequencing techniques (next generation sequencing; NGS), with the capability to analyse multiple genes or entire genomes, have been rapidly adopted into research. This study examines the possibility of incorporating NGS into a clinical UK service context.
Methods The study applied NGS of 105 genes to 50 patients known to be affected by inherited forms of blindness in the setting of a UK National Health Service-accredited diagnostic molecular genetics laboratory. The study assessed the ability of an NGS protocol to identify likely disease-causing genetic variants when compared with current methodologies available through UK diagnostic laboratories.
Results Conventional testing is only applicable to the minority of patients with inherited retinal disease and identifies mutations in fewer than one in four of those patients tested. By contrast, the NGS assay is directed at all patients with such disorders and identifies disease-causing mutations in 50–55%, which is a dramatic increase. This includes patients with apparently ‘sporadic’ disease, and those for whom clinical management and prognosis are altered as a consequence of defining their disease at a molecular level.
Conclusions The new NGS approach delivers a step change in the diagnosis of inherited eye disease, provides precise diagnostic information and extends the possibility of targeted treatments including gene therapy. The approach represents an exemplar that illustrates the opportunity that NGS provides for broadening the availability of genetic testing. The technology will be applied to many conditions that are associated with high levels of genetic heterogeneity.
- Next generation sequencing
- retinitis pigmenttsa
- retinal dystrophy
- academic medicine
- clinical genetics
- molecular genetics
JO and BGM contributed equally to this research.
Funding This work was supported by Fight for Sight (Programme Grant 1801), RP Fighting Blindness (Grant GR547) and the Manchester National Institute for Health Research Biomedical Research Centre.
Competing interests None.
Ethics approval Ethics approval was provided by NW Research Ethics Committee (10/H1005/48).
Provenance and peer review Not commissioned; externally peer reviewed.