DNA Test Detects Mutations Across Multiple Genes

The first multigene DNA sequencing test that can help predict cancer patients' responses to treatment has been launched in the United Kingdom.

The test uses the latest DNA sequencing techniques to detect mutations across 46 genes that may be driving cancer growth in patients with solid tumors and the presence of a mutation in a gene can potentially determine which treatment a patient should receive.

Scientists at the Oxford Biomedical Research Center (UK) launched the DNA test for the UK National Health Service (NHS; London, UK).The number of genes tested marks a step change in introducing next-generation DNA sequencing technology into the NHS, and heralds the arrival of genomic medicine with whole genome sequencing of patients just around the corner.

The test costs around GBP 300 and could save significantly more in drug costs by getting patients on to the right treatments straightaway, reducing harm from side effects as well as the time lost before arriving at an effective treatment. The test is run on a next generation sequencing platform called the Ion Personal Genome Machine (Life Technologies Corporation, Carlsbad, CA, USA). The test and accompanying software have been substantially modified as requested by the Oxford team to fulfill diagnostic standards in their laboratory.

The scientists have carried out tests and comparisons to verify the robustness of the technique with cancer biopsies direct from patients. The team compared the new 46-gene test against conventional techniques for 80 consecutive cancer biopsies in the hospital laboratory's workflow. The next-generation DNA sequencing method detected all the mutations the conventional method did. It also detected new mutations the conventional method did not, and detected mutations present at much lower levels in the samples. The time taken for the 46-gene test also fitted into the standard turnaround time for samples at the laboratory. The test requires a very small amount of 5 ng of DNA, an advantage when working with clinical samples that are typically limited in quantity.

Jennifer Taylor, MD, of the Wellcome Trust Center for Human Genetics (Oxford, UK) said, "'We wanted a test that would use the latest DNA sequencing techniques to detect a wide range of mutations in a wide range of genes. The test should be able to cover more cancers and more treatments, all for a similar cost to conventional methods. It's a significant step change in the way we do things. This new 46 gene test moves us away from conventional methods for sequencing of single genes, and marks a huge step towards more comprehensive genome sequencing in both infrastructure and in handling the data produced."

Related Links:
Oxford Biomedical Research Center
Life Technologies Corporation
Wellcome Trust Center for Human Genetics