A test that aims to rule out autism using a strand of hair is now available to the public

NBC News

06-02-2025

The Summary
A test designed to identify biomarkers associated with autism just became available in most states.
The test is meant to help physicians rule out autism in children who have higher likelihoods of it.
The results are based on a metabolic analysis that requires just a strand of hair, but experts say more research is needed.
A test designed to identify biomarkers associated with autism in infants and young children is now available to the public in most states.
LinusBio, a New Jersey-based startup, on Thursday launched the test, called Clearstrand-ASD, which it says can help physicians rule out autism in children 1 to 36 months old. The test requires just a single strand of hair.
The test cannot diagnose autism spectrum disorder, nor is it designed to be used on its own. Instead, it is meant to help physicians rule out autism in children who have higher likelihoods of it. That could be because a kid has a sibling with autism or has demonstrated behaviors associated with the disorder.
Manish Arora, a co-founder of LinusBio and its CEO, said Clearstrand-ASD is the only biochemical test available to detect autism spectrum disorder in children younger than 18 months. He hopes it will make the process of ruling out autism more efficient and reduce the wait for those in most need of intervention or treatment.
'The focus is really on early intervention,' Arora said. 'The earlier you intervene, the better off children are.'
The test uses children's hair strands to analyze their metabolic histories, which tell the story of the substances or toxins they have been exposed to or have processed over time, Arora previously told NBC News. His research has identified patterns of dysregulation in exposure to or metabolism of metals that some evidence suggests could be associated with autism. Hair can offer a kind of timeline of what was going on in a child's body, including patterns of metal exposure, during specific developmental stages.
'We can detect the clear rhythm of autism with just about 1 centimeter of hair,' Arora previously told NBC News, comparing the dynamic to the way a tree's rings can tell the story of what the environment was like at a particular time in its growth.
The Food and Drug Administration has not approved the Clearstrand-ASD test. But as of Thursday, it is available to consumers in 44 states — if they are able to pay the $2,750 cost. (It is not yet eligible for insurance coverage.) The test can be ordered by a primary care provider or directly through LinusBio, which sets up a telehealth appointment with an independent physician it provides, Arora said.
'You come to us, you get a prescription from an independent clinician. We send out the kit to you. You get the result all within about three weeks,' he said.
The diagnostic aid is still early in its development, and data supporting its effectiveness is limited. At the Metabolomics and Human Health Conference in Ventura, California, on Thursday, LinusBio shared some new, initial findings. In a group of 490 children in California with elevated risk of autism spectrum disorder, the test was able to rule it out with about 92.5% accuracy, the company said. However, the results have not been published in a peer-reviewed journal.
A 2022 study of the company's methodology, published in the Journal of Clinical Medicine, analyzed a different LinusBio test that is still in development and found that the methodology accurately predicted autism diagnoses — positives and negatives — about 81% of the time.
The test is one of several promising ideas that researchers are pursuing as ways to identify or rule out autism early in a child's life. Other scientists are looking into eye-tracking, blood testing and audio analysis as possible methods.
Clearstrand-ASD works by running a laser over the length of hair being tested, which turns the hair into a plasma that can be processed by machine-learning algorithms. Results from the full analysis are expected within three weeks, after which a child's parents join a follow-up telehealth appointment.
Outside experts said LinusBio's hair strand test has shown promise but needs more research.
'To me this feels like it's on the earlier side of things, not the earliest. They have some compelling results,' said Stephen Sheinkopf, a professor of pediatrics at the University of Missouri School of Medicine and the Thompson Center for Autism and Neurodevelopment. 'This seems like an approach that has the potential to be part of a suite of ways we can screen children for concerns, but it's, to me, at the stage of needing more evidence.'
Sheinkopf suggested that families with young children who are worried about the possibility of autism work closely with pediatricians or primary care physicians who carefully monitor the children's development and screen them for autism.
'Sometimes we see the shiny new tool — we want to skip over the things that are already available,' he said.
Sheinkopf also noted that parents who have evidence of differences in their child's development can seek federally mandated services without a formal diagnosis.
Seeking an autism diagnosis for a child can take a long time. The American Academy of Pediatrics recommends autism screenings at 18 months and 24 months. Neurological examinations, language assessments, behavior observations and other methods are ultimately used to diagnose a child.
Arora said he hopes that by helping rule out autism for some children, his company's test could prioritize attention for those most in need and reduce the wait times for families seeking care or treatment.
Rebecca Landa, executive director of the Center for Autism Services, Science and Innovation at the Kennedy Krieger Institute, a pediatric care center in Baltimore focused on developmental disabilities, said there is a shortage of specialists to diagnose and help treat autism. So she hopes the test could make the flow of children to specialists more efficient.
'That could accelerate the rate at which children get seen. And so that way, the children who are very low likelihood for autism are not sitting in the pipeline waiting to see a certain kind of specialist,' she said.