Scientists have developed a blood test that can detect motor neurone disease in its earliest stages with 97 per cent accuracy – even before symptoms strike.
The test was developed by researchers at the US-based not-for-profit Brain Chemistry Labs, who analysed 788 blood samples – roughly half from patients with the disease and half from people without it.
Motor neurone disease, also known as amyotrophic lateral sclerosis (ALS), is a rare, progressive neurological condition that affects the nerves controlling movement, rapidly leading to muscle weakness, paralysis and death.
The scientists focused on microRNAs – tiny fragments of genetic material found in the blood that help regulate how cells function.
Patterns of these microRNAs can change when disease is present, meaning they have the potential to act as biomarkers – biological signs that someone has a particular illness.
In this case, the researchers identified eight specific microRNAs linked to motor neurone disease. The biomarker parameters were first established using 449 individual blood samples.
The team then used a laboratory technique known as quantitative polymerase chain reaction (qPCR) to rapidly analyse the remaining samples and assess how accurately the test could diagnose the condition.
They found the blood test correctly identified patients with motor neurone disease 97 per cent of the time and accurately ruled it out in 93 per cent of people who did not have the illness.
A new test has been developed that can detect ALS, the most common type of motor neurone disease with nearly 100 per cent accuracy
Dr Rachel Dunlop, a senior researcher at the non-for-profit, said the test could allow patients to begin treatment earlier in the course of the disease.
‘This new test means that patients can initiate therapy early in the disease,’ she told MedicalXpress.
Researchers say the test could help address one of the biggest problems facing people with motor neurone disease – long delays in diagnosis.
‘For ALS, which typically results in loss of life within 2–5 years from the appearance of symptoms, a delay of one year in receiving a diagnosis is simply unacceptable,’ said Dr Paul Alan Cox, executive and co-founder of Brain Chemistry Labs.
He added: ‘The ALS patient population is deeply underserved.
‘That’s why, as a not-for-profit organization, we have doggedly pursued development of this new diagnostic test.’
Following the results, Dr Sandra Banack said the team is now seeking to move the test beyond the laboratory.
‘We are seeking to identify a diagnostic firm to make this test commercially available,’ she said.
England rugby legend and World Cup winner Lewis Moody recently revealed he had been diagnosed with motor neurone disease (MND) at just 47
The illness took the life of former rugby leage star Rob Burrow, who was diagnosed in 2019
Dr Banack and Dr Dunlop presented their findings, recently published in the journal Molecular Neurobiology, at the International Symposium on ALS/MND last week.
Around 5,000 adults in the UK are currently living with motor neurone disease, of which ALS is the most common form. The condition affects the nerves that control movement, leading to progressive muscle weakness, loss of speech and difficulty breathing.
For most patients, life expectancy is between two and five years from the onset of symptoms, although the speed of progression can vary widely.
The disease has recently been thrust back into the spotlight after former England rugby union international Lewis Moody revealed earlier this year that he had been diagnosed with motor neurone disease, despite previously being fit and healthy.
It also followed the death of former rugby league star Rob Burrow, who was diagnosed in 2019 and became a powerful campaigner for greater research funding and improved care for patients living with the condition.
The condition was also highlighted earlier this year when actor Eric Dane, 53, best known for playing Dr Mark Sloan in the TV series Grey’s Anatomy, revealed that he had been diagnosed.
Perhaps the most famous case was that of physicist Professor Stephen Hawking, who lived with motor neurone disease for more than 40 years after being diagnosed in his early 20s – far longer than most patients.
Experts say earlier and more accurate diagnosis could allow patients to access specialist care, symptom-relieving treatments and clinical trials sooner, even though there is currently no cure.
Famed physicist Stephen Hawking was diagnosed with amyotrophic lateral sclerosis (ALS)
Eric Dane, an actor, has also said that he has been diagnosed with ALS
Motor neurone disease is usually diagnosed between the ages of 55 and 75, with symptoms that worsen steadily over time.
Early signs can include muscle twitches, a weak grip, weakness in the leg or ankle, slurred speech and unexplained weight loss.
There is currently no cure, and the disease progressively robs patients of their ability to walk, speak and eventually breathe.
However, researchers say recent genetic discoveries may help explain why the disease develops and could point towards future treatments.
In a study published earlier this year, scientists identified 423 ultra-rare genetic variants shared by people with ALS and those with another motor neurone condition, hereditary spastic paraplegia (HSP).
Although the two diseases progress differently – with muscle weakness in ALS potentially beginning in the arms, legs, head or neck, while HSP typically starts in the legs – the overlap suggests shared biological mechanisms.
Dr Gang Wu, a statistician who led the research, said rare genetic variants in motor neurone diseases have often been overlooked.
He said: ‘By analysing a large dataset with multiple related motor neuron disorders, we found that genes associated with HSP could also increase the risk for sporadic ALS.’
Researchers say the findings could help scientists better understand who is at risk of developing ALS and, in time, support the development of new treatments.
