"Scientists in Britain say they have developed a blood and urine test that can detect autism in children. Researchers at the University of Warwick said the test believed to be the first of its kind could lead to earlier diagnosis of autism spectrum disorders ASD in children who could then be given appropriate treatment much earlier in their lives. ASDs mainly affect a persons social interaction and communication with symptoms that can include speech disturbances repetitive andor compulsive behaviour hyperactivity anxiety and difficulty adapting to new environments. As there is a wide range of ASD symptoms diagnosis can be difficult and uncertain particularly at the early stages of development. It is estimated that about one in every  people in the UK has ASD with more boys diagnosed with the condition than girls. Scientists said their research found a link between ASD and damage to proteins in blood plasma. They found the most reliable of the tests they developed was examining protein in blood plasma which found children with ASD had higher levels of the oxidation marker dityrosine DT and certain sugarmodified compounds called advanced glycation endproducts AGEs. Genetic causes are thought to be responsible for about a third of cases of ASD while the rest are believed to be caused by a combination of environmental factors mutations and rare genetic variants. However researchers believe their new tests could reveal yettobeidentified causes of ASD. They also confirmed the previously held belief that mutations of amino acid transporters are a genetic variant associated with ASD. The Warwick team worked with collaborators at the University of Bologna in Italy who recruited  children who had been diagnosed with ASD along with a control group of  other children between the ages of five and . Blood and urine samples were taken from the children for analysis. The Warwick team discovered there were chemical differences between the two groups. Working with a further collaborator at the University of Birmingham the changes in multiple compounds were combined using artificial intelligence algorithm techniques to develop a mathematical equation to distinguish between ASD and healthy controls. The outcome was a diagnostic test better than any existing method. They said the next steps were to repeat the study with further groups of children to confirm the good diagnostic performance and to assess if the test could identify ASD at very early stages indicate how the ASD is likely to develop further to more severe disease and assess if treatments were working. The research was led by Naila Rabbani reader of experimental systems biology at the University of Warwick who said Our discovery could lead to earlier diagnosis and intervention. We hope the tests will also reveal new causative factors. With further testing we may reveal specific plasma and urinary profiles  or fingerprints  of compounds with damaging modifications. This may help us improve the diagnosis of ASD and point the way to new causes of ASD. The research has been published in the journal Molecular Autism https  Note added  February  The UK autism research charity Autistica provided the following comment to the Guardian This is a small earlystage study which may explain one biological difference in autism. At this stage the results presented are not strong enough to suggest that this method could be used for the diagnosis of autism. For example we dont know whether this technique can distinguish autism from ADHD anxiety or other similar conditions. There have been many previous attempts to develop a biological test for autism. Still the best way to diagnose autism is through clinical interview and observation which takes into account the many features of autism."