New test detects autism in very young children
Scientists have developed method to detect autism in younger by testing their saliva,
Researchers found a set of 32 RNA factors in saliva that can accurately distinguish children with autism spectrum disorder, or ASD. The factors could potentially develop an objective biomarker-based test.
Steven Hicks, of the Pennsylvania State College of Medicine, and Frank Middleton, of SUNY Upstate Medical University, along with scientists from Quadrant Biosciences, analysed the RNA of over than 450 children between the ages of 18 months and 6 years old. With 85% accuracy, they found differences in 238 children with autism spectrum disorder, or ASD, from 218 children showing normal typical developmental delay.
The researchers used next-generation sequencing to measure RNAs in the saliva, using a machine-learning algorithm for the first 372 children. They validated the remaining 84 children’s samples without the machine learning, in order to the expand the investigative method of the genomic, physiologic, microbiome and environmental factors that cause ASD.
“Growing evidence suggests that autism arises from interactions between a child’s genes and the environment,” Hicks said.
“This study measured factors that may control interactions between genes and the environment, especially the microbiome.”
Current screening uses the Modified Checklist for Autism in Toddlers Revised, or MCHAT-R, a parent-based test that generally takes over a year to render results and often turns up false positives.
In the US, the average age for ASD diagnosis is above the age of four. The earlier the diagnosis, the sooner experts can deliver intensive treatment, which can improve autism symptoms in children.
“The ability to accurately discriminate between children with autism and their peers with non-ASD developmental delay is of paramount importance in the field,” Middleton said.
“While the algorithm is not designed as a screening tool, it can provide valuable information in children with a positive MCHAT-R screen, over 80% of whom will not have ASD. In this way, it can be used to prioritize specialist referral or to provide an objective aid to an autism diagnosis,” Middleton said.
