Blood test for autism

A biochemical test for autism has been developed by scientists in the US...

The one per cent of children diagnosed with autism and “autism spectrum disorders” struggle in social situations, find communication a challenge, may have behavioural problems and frequently fall behind at school.

At the moment, the diagnosis is only made clinically - by a specialist assessing a child; there’s currently no biochemical test for the condition, which means most diagnoses are also made “late”, possibly missing an opportunity to intervene therapeutically at an earlier stage. Now that might be about to change. 

Writing in PLoS Computational Biology, Juergen Hahn, from Rensselaer Polytechnic Institute in the US, has compared blood samples collected from a group of 83 autistic children with blood samples from 76 unaffected volunteer controls and found a signature change in a range of biochemical markers that are significantly altered in the autistic patients.

The metabolic data allowed the researchers to classify correctly 97.6 percent of the children with autism and 96.1 percent of the normal children. The degree of abnormality in the blood tests also predicted the severity of the child's autism.

"We can use this set of markers to pick up potential cases much earlier," Juergen explains.

The signature chemicals included markers of biochemical stress and also metabolites involved in the epigenetic modification of DNA. He acknowledges, though, that, at this stage, it's not clear whether these biochemical features will be present from birth, "although that is likely. We still need to test that."