Blood test 'could revolutionise diagnosis of autism'
OXFORD, UK: A simple test that could revolutionise the diagnosis of autism could be available within just three years.
The kit would use a few drops of blood to help doctors decide if a child has the devastating condition, speeding up diagnosis and allowing life-altering treatment to start earlier.
The test, which Oxford University researchers believe could be in NHS clinics by 2013, would capitalise on the results of a landmark genetic study into the root causes of autism.
In the largest study of its kind, 120 scientists and doctors from 50 universities around the world compared the DNA of more than 1,000 children with autism and their parents with the genetics of more than 1,300 other people.
They found that in autism, large chunks of DNA are likely to be duplicated or erased, damaging genes and interrupting their vital work.
The children involved had many different insertions or deletions - known as copy number variants - but the end result was the same, the journal Nature reports.
Some of the damaged genes are key to the development of the brain and the transmission of messages.
Although some were known to be involved in autism before, others have been implicated in the condition for the first time.
Autism and related conditions such as Asperger's syndrome affect more than one in 100 British children - ten times as many as just 30 years ago.
With the causes unclear, diagnosis is a lengthy and stressful process of hospital visits and psychological tests, and there are not drugs that can tackle the condition at its root.
The latest research shines a light on the causes, providing scientists with the information they need to formulate drugs and create blood tests.
Experts said it brought hope of a "brighter future" to the millions of families who struggle with autism every day.
Canadian researcher Dr Stephen Scherer said: "The results will lead to a paradigm shift when it comes to understanding the root causes of autism."
Professor Tony Monaco, who led the Oxford team, likened autism research to trying to put together a jigsaw - with the latest findings equivalent to the vital pieces that make up the edges.
He said: "This consortium of scientists and clinicians has really been trying to put together a very large jigsaw puzzle without having the benefit of a nice colourful picture on the box.
"In this paper the copy number variants that we have found were probably the easiest thing we could have found. They frame this jigsaw puzzle, they are the pieces with the edges. And they give us an idea of what the picture may look like because you can group them together and say that some are representing the sky or the ocean or the sand of the picture."
Tests that pick up copy number variants are already used in the diagnosis of learning disabilities and the professor and Newcastle University colleagues are poised to carry out a pilot study of a test for autism.
He said: "Just knowing about these genetic changes can help families come to terms with why their child has autism but can also be important where there are siblings too in determining future risk."
The results would allow parents to be counselled on the odds of their having a further child with the condition. However, it would only pick up 15 to 20 per cent of cases - although further genetic studies could improve on this.
Trinity College Dublin researcher Dr Louise Gallagher said: "Currently autism diagnosis is entirely behavioural and lengthy and parents are subjected to a long process where their child is being assessed and some children are not getting a diagnosis until as late as five years old.
"With earlier detection, these children could get earlier interventions which may limit the severity of the condition."
Dr Geri Dawson, of the US charity Autism Speaks, which part-funded the study, said: "These findings bring hope to many families who struggle with autism every day."
Dr Jenny Longmore, of the British charity, Autistica, which also provided funding, said: "It is a giant leap forward."
But the National Autistic Society cautioned that the fruits of the research were a long way off - and said that autistic children and adults need more support in the here and now.
For instance, many children with autism are not receiving the help they need to deal with
associated mental health problems such as depression and obsessive compulsive disorders.
The charity's Dr Gina Gómez de la Cuesta said: "Research into autism is constantly evolving but the exact causes are as yet still unknown. The difficulty of establishing gene involvement is compounded by the interaction of genes with the environment. Genetic testing for autism is still a long way off, given that autism is so complex.
"Whilst it is very important that research continues, it is also crucial that those living with the condition have access to appropriate advice and information, as the right support at the right time can make an enormous difference to people's lives."
Scientists at Imperial College London are also developing a diagnostic test but it is based on research showing that people with autism have different bugs in their guts from others.
(Source: July 3, 2010) |
