Researchers develop single blood test for all known inherited heart conditions
Previous tests have only been able to pick up specific conditions
Friday, 19 February 2016
An international team of researchers has developed a new blood test for all known inherited heart conditions, reports the Journal of Cardiovascular Translational Research.
The team found that by looking at a particular group of genes they were able to reliably test for all known inherited heart conditions, using just one blood test.
Previous genetic tests for inherited heart conditions have looked at a smaller number of genes and were only able to identify specific conditions. These tests were also generally more expensive, and time consuming, meaning that it took longer to make a diagnosis—something that has proved a major barrier to the nationwide roll-out of genetic testing in the NHS.
The new test is quicker and more reliable than previous tests, says the British Heart Foundation (BHF), which helped fund the study.*
There are many different types of inherited heart conditions so diagnosing the exact condition and gene causing it is key to effective treatment. For many people, the first sign that they have one is when a member of their family dies suddenly with no obvious explanation.
Genetic testing of relatives can identify those who carry the faulty gene, and options, such as surgery, medication or lifestyle changes offered, to reduce the risk of sudden death.
Dr James Ware, one of the lead researchers at Imperial College London, and a consultant cardiologist at the Royal Brompton Hospital, said: "Genetic tests are invaluable when managing inherited heart conditions. They can help to make the initial diagnosis, and to choose the best treatment for the affected person. But where they make the biggest impact is in looking after that person's family.”
"Without a genetic test, we often have to keep the whole family under regular surveillance for many years, because some of these conditions may not develop until later in life. This is hugely costly for both the families and the health system."
BHF medical director, Professor Peter Weissberg, said: "As research advances and technology develops, we are identifying more and more genetic mutations that cause these conditions. In this rapidly evolving field of research the aim is to achieve ever-greater diagnostic accuracy at ever-reducing cost.
"This research represents an important step along this path. It means that a single test may be able to identify the causative gene mutation in someone with an inherited heart condition thereby allowing their relatives to be easily tested for the same gene."
Dr Yalda Jamshidi, senior lecturer in Human Genetics, Cardiovascular and Cell Sciences Institute, St George’s, University of London commented: “Genetic DNA testing is commonly used for diagnostic purposes in many clinical settings. Inherited heart conditions can be the result of changes in the DNA sequence of various genes. DNA sequencing technology can be used to identify these disease causing changes.”
“The current study describes a new test whereby a combination of the genes previously implicated in cardiac conditions are sequenced together. The new panel shows some improvement over existing tests which have more limited numbers of genes included, and also more accurate results than DNA tests which aim to sequence all of the genes in the genome,” she said.
But she cautioned: “The new panel is more comprehensive than existing smaller DNA test panels, however ultimately the difficulty with screening more and more genes will be in accurately determining which of the variants identified are indeed responsible for the disease.”
* Chee Jian Pua, et al. Development of a Comprehensive Sequencing Assay for Inherited Cardiac Condition Genes. Journal of Cardiovascular Translational Research, February 2016, pp 1-9. DOI: 10.1007/s12265-016-9673-5