Heart defects that kill young people in the prime of their lives could soon be cured with a simple injection.
Pioneering scientists at Oxford University and Harvard University in the US will trial the first proven cure for genetic heart muscle diseases by rewriting a letter of patients’ DNA.
Such devastating undiagnosed conditions have seen a host of professional footballers resuscitated after suffering heart attacks while playing.
The teenage son of Welsh footballing legend Terry Yorath died during a garden kickabout and they were also the cause of fatal on-pitch heart attacks for ex-West Ham midfielder Marc-Vivien Foe.
Inherited cardiomyopathy diseases affect an estimated 260,000 Brits but within just a few years they could be cured by gene editing.
Healthy versions of the gene will be injected in to the arm and mutations added to silence the faulty genes to prevent dangerous heart tissue scarring.
Scientists hope the CureHeart technology could one day be used to correct non-inherited heart damage such as coronary heart disease.
CureHeart project lead Prof Hugh Watkins, of Oxford University, said: “This is our once-in-generation opportunity to relieve families of the constant worry of sudden death, heart failure and potential need for a heart transplant.
“After 30 years of research, we have discovered many of the genes and specific genetic faults responsible for different cardiomyopathies, and how they work. We believe that we will have a gene therapy ready to start testing in clinical trials in the next five years.
“This absolutely is something that will work in the end, it’s just a question of time.”
Cardiomyopathy is a general term for diseases of the heart muscle, where the walls of the heart chambers have become stretched, thickened or stiff, affecting its ability to pump blood around the body.
Such genetic defects are the cause of half of heart transplants and are the leading cause of heart death in young people.
The Mirror is campaigning for greater availability of defibrillators in public places to help young adults who suffer one.
Every week 12 people under the age of 35 die in the UK of an undiagnosed heart condition, very often caused by an inherited heart muscle disease, also known as genetic cardiomyopathy.
One in every 250 people are affected and they have a 50/50 chance they will pass the defect on to their offspring.
Some are less severe and never discover their problem until it is identified in their children.
Prof Watkins, who is leading the international team developing the CureHeart technology, added: “When you hear about any young person who dies suddenly playing sport, it could be one of these conditions. You look at their family, and they’ll have siblings in the same situation.
“Families who carry this mutation live in fear. This is really common.
“There will be one or two pupils in every school, every GP surgery will have several patients with these conditions.
“But there’s quite a wide range of severity and some patients get away without too much trouble. But others present early.
“They all have in common that they can cause progressive heart failure where the heart can’t pump enough, or life threatening or life ending heart rhythms.”
The treatment will initially be trialled in adults whose condition has progressed and who are awaiting heart transplants. The hearts will then be removed and the changes analysed.
It could eventually be given to children identified via their parents and born with the genetic mutation, before heart disease develops.
Dr Christine Seidman, CureHeart co-lead from Harvard Medical School, said: “We cardiologists are able to deliver lots of medicines to the heart, but never before have we been able to deliver cures.
“Most of the mutations that we find in our human patients they all frequently will alter one single letter of the DNA code.
“That has raised the possibility that we could alter that one single letter and restore the code so that it is now making a normal gene, with normal function.”
In hearts with genetic cardiomyopathy the tissue slowly becomes scarred over time and function is impaired.
The condition nearly claimed the life of footballer Fabrice Muamba who suffered a heart attack while playing for Bolton Wanderers in 2012.
Delivering a healthy copy of the faulty gene via an injection can enable the production of proteins that result in normal heart function.
CureHeart’s team of leading experts from the UK, US and Singapore have been granted £30 million from the British Heart Foundation to perfect its technology, following a research funding competition judged by Sir Patrick Vallance.
Clinical trials will now work out the best way to silence the faulty genes they have identified and minimise the risk of “off target” changes to other healthy genes.
Sir Patrick, the UK’s Chief Scientific Adviser, said: “CureHeart was selected in recognition of the boldness of its
ambition, the scale of its potential benefit for patients with genetic heart muscle diseases and their families, and the excellence of the international team of participating researchers.”
The team will use precision genetic techniques, called base and prime editing, in the heart for the first time.
Animal studies have already shown the techniques work.
Prof Sir Nilesh Samani, medical director at the BHF, said: “This is a defining moment for cardiovascular medicine.”