September 18, 2024 | The push in personalized medicine to look beyond the genome has netted quite a few valuable ‘omics technologies. “In certain areas genomics alone cannot fully explain health and disease, and brain health is one of those regions,” said Manish Arora, CEO and founder of LinusBio. LinusBio is tracking environmental exposures recorded over time in hair. Arora believes the platform will “revolutionize personalized medicine.”
Genomic sequencing is valuable, but it has not yet helped us predict who will get conditions like autism and ADHD, Arora told Diagnostics World. That’s where environmental exposures—both before and after birth—come into play. “The field has recently been christened as ‘exposomics’,” Arora said, comprising a body’s exposures over time. The Linus Bio platform works primarily with a strand of hair, and Arora says testing hair can yield the time data you’d gain from 500 to 1,000 blood samples.
“The reason we focus on the time dimension is—unlike our genetic sequence, which is set at conception and we carry that throughout our life with some minor epigenetic changes—our exposome is constantly changing,” he said. “Just looking at the static genome doesn’t really tell you how our body is running.” He likens it to looking at the blueprint of a car, which, while accurate, still doesn’t relate the quality of the driving or the experiences of the passengers over time.
Arora started looking to map early exposures that might lead to autism spectrum disorder. His initial tissue of interest was baby teeth, which develop during infant- and childhood and fall out painlessly at expected times. In 2018, Arora was an author on a Science Advances paper testing whether zinc-copper cycles, which regulate metal metabolism, are disrupted in autism spectrum disorder (DOI: 10.1126/sciadv.aat1293). The team studied twins in Sweden and collected their baby teeth after they fell out naturally from 75 participants (32 complete twin pairs and 11 individuals from twin pairs whose sibling did not donate a tooth). The team supplemented the twin study with 118 samples from the US and UK.
“We went to the UK, we went to Texas and New York, and all sorts of places and collected these baby teeth that moms and dads had been storing from their babies,” he said. “But baby teeth shed by the age of 5-6 years; by then autism is already full blown.”
Arora wanted a different, non-invasive tissue that could be collected at home, and used to intervene earlier in children at risk. He turned his attention to hair. In 2023, Arora and several others of the same team published new work in the Journal of Clinical Medicine detailing how elemental uptake and metabolism measured in hair samples can yield an effective signal predictive of autism diagnosis (DOI: 10.3390/jcm12031022).
In the meantime, Linus Biotechnology raised about $1.5M in a seed round in March 2022. In November 2022, Arora, Paul Curtin, and Christine Austin (both authors on the papers above) filed a patent application for “Devices, systems, and methods for topographic analysis of a biological surface.”
“The core idea is the same,” says Arora of the company’s focus on hair. “In fact, the instrumentation is the same as well, but you switch the matrix from baby teeth to hair.”
One centimeter of hair gives 800-1,000 time points in a month, Arora said. The LinusBio platform can scan those timepoints and recognize patterns associated with autism spectrum disorder, ADHD, and more. Those patterns are recognizable in even a centimeter, Arora said, but are made clearer over longer lengths of time (and hair).
For more time sensitive exposome questions—for instance, if someone traveled or experienced an environmental exposure at a certain date—measuring back centimeter by centimeter is like moving backward a month at a time.
Linus Bio has received a breakthrough designation from FDA for an autism biomarker, but Arora emphasizes that the company is not just an autism diagnostic company. His vision is to test every newborn for biomarkers tied to autism, ADHD, eventually ALS, and more. “We’re also working with pharma companies to develop drugs,” he said, and related a population health collaboration with the Japanese government and several academic partnerships in the US and Europe.
The platform is not limited to teeth or hair samples, either. The company is measuring biomarkers in blood, urine, stool, saliva, and breast milk as well, though those samples don’t reflect change over time the way hair does. In all cases, the Linus Bio platform looks at not only known exposures, but how the body responds. “The next best question is how are you metabolizing your exposures,” Arora asks. “How are you handling that? How are you excreting them? That’s where the time dimension comes in.” The company’s active partnerships are further developing the research and innovation.
“This platform is being used to really look at human physiology in a completely new way,” he said. “That’s the mission of the company.”