New blood and urine tests that can indicate autism in children have been developed by researchers in England.
The researchers, who discovered a link between autism and damage to proteins in blood plasma, say the tests could led to earlier detection of autism spectrum disorders (ASD) and earlier intervention.
“We hope the tests will also reveal new causative factors,” said Dr. Naila Rabbani, Reader of Experimental Systems Biology at the University of Warwick, who led the study. “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 researchers explain they found a link between ASD and damage to proteins in blood plasma by oxidation and glycation; processes where reactive oxygen species (ROS) and sugar molecules spontaneously modify proteins.
They found the most reliable of the tests they developed was examining protein in blood plasma where, when tested, children with ASD were found to have higher levels of the oxidation marker dityrosine (DT) and certain sugar-modified compounds called “advanced glycation endproducts” (AGEs).
Genetic causes have been found in 30 to 35 percent of cases of ASD, while the remaining 65 to 70 percent of cases are thought to be caused by a combination of environmental factors, multiple mutations and rare genetic variants. The research team said they believe the new tests could reveal yet to be identified causes of ASD.
The team’s research 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 38 children who were diagnosed with ASD (29 boys and nine girls) and a control group of 31 healthy children (23 boys and eight girls) between the ages of five and 12. Blood and urine samples were taken from the children for analysis.
The Warwick team discovered that 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 together using artificial intelligence algorithms techniques to develop a mathematical equation or algorithm to distinguish between ASD and healthy controls. The outcome was a diagnostic test better than any method currently available, according to the researchers.
The next steps are to repeat the study with further groups of children to confirm the good diagnostic performance and to assess if the test can identify ASD at very early stages, indicate how the ASD is likely to develop further to more severe disease, and assess if treatments are working, the researchers explained.
The study was published in Molecular Autism.
Source: University of Warwick