New blood test detects deadly inherited heart conditions

A new genetic test to improve diagnosis in people with inherited heart conditions has been developed by researchers.

The researchers showed that by looking at a particular group of genes they were able to reliably test for all known inherited heart condition genes with one simple test. The findings have been published in the Journal of Cardiovascular Translational Research.

Previous genetic tests for inherited heart conditions looked at a smaller number of genes and were only able to identify specific conditions, leading to greater costs, more work, and ultimately longer before a diagnosis could be made. This has been a major barrier to the nationwide rollout of genetic testing in the NHS.

The new test, which is available to testing labs in the UK and overseas, is quicker and more reliable than previous tests, reducing costs and allowing patients to be diagnosed quickly and accurately. It is the result of an international collaboration between researchers in Singapore, Imperial College London and at the MRC Clinical Sciences Centre, funded by the British Heart Foundation.

This group of diseases affect over half a million people in the UK. They can affect people of any age, and can be life threatening. 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 an inherited heart condition is when a member of their family dies suddenly with no obvious explanation.

Genetic testing on family members can then identify those who carry the faulty gene and steps can be taken to reduce the risk of sudden death, such as surgery, medication or lifestyle changes. However, sometimes genetic tests are not as reliable as they could be and can miss critical genes which can cause problems for patients with complex diagnoses.

The test, which looks at 174 genes, has already been rolled out at Royal Brompton & Harefield NHS Foundation Trust with approximately 40 patients per month being successfully tested for an inherited heart condition.

Dr James Ware is one of the lead researchers at the MRC Clinical Sciences Centre at  Imperial College London and a Consultant Cardiologist at Royal Brompton Hospital. He 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.

“By contrast, when a genetic test reveals the precise genetic abnormality causing the condition in one member of the family, it becomes simple to test other family members. Those who do not carry the faulty gene copy can be reassured and spared countless hospital visits.

“This new comprehensive test is increasing the number of families who benefit from genetic testing.”

Professor Peter Weissberg, Medical Director at the British Heart Foundation, which funded the research, said: “Collectively, inherited heart conditions represent a major cause of heart disease and are often the cause of an unexplained sudden death in a young person.

“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.”

This research was also funded by the Health Innovation Challenge Fund Grant, which is a partnership between the Department of Health and the Wellcome Trust, and was supported by the NIHR Cardiovascular Biomedical Research Unit.