Invented by Kong; Xue-Jun, Dong; Cun-Jian

Autism Spectrum Disorder (ASD) can be a lifelong challenge for children and their families. What if we could spot signs of risk before a child’s second birthday, when the brain is most flexible? A new patent application points to a simple, lab-based way to assess ASD risk in infants—by measuring a helpful gut bacterium called Limosilactobacillus reuteri (L. reuteri). In this article, we’ll explore why early diagnosis matters, how this method fits into current science, and what makes this invention stand out.

Background and Market Context

ASD now affects about 1 in 44 children in the United States. This number has grown quickly over the past few decades. The impact is huge, not just for each child and family, but for society as a whole. Many children with ASD need care and support throughout their lives. This leads to big costs—over $223 billion in 2020, and possibly reaching $589 billion by 2030 in the U.S. alone. But beyond dollars, the emotional toll can be overwhelming for families.

Right now, most children are diagnosed around age two or later. That’s because the signs of ASD—like trouble with social skills or repetitive behaviors—usually become clear only after a child is a toddler. Diagnosis is based on watching how a child behaves, using tools like the DSM-5 or the ADOS-2. These are expert checklists, but they depend on trained observers and a child’s age. For parents and doctors, waiting two years or more for answers can feel like forever.

Early help is the gold standard. Studies show that when children get support or therapy before age two, they often do better in the long run. Their brains are more able to adapt and change. But since there are not yet any reliable lab tests for ASD in very young children, early intervention usually waits for clear symptoms. This leaves many high-risk kids—such as those with siblings who have ASD—without the chance to get ahead of the curve.

Families, doctors, and health systems have been searching for a way to spot ASD risk earlier, before behaviors appear. A blood test, a stool test, any kind of lab marker could make a world of difference. Not only could it help start therapy sooner, it could bring peace of mind or clear next steps for worried parents. That’s where this new approach, centered on L. reuteri, could shake things up.

Scientific Rationale and Prior Art

The gut and the brain are more connected than many people realize. In the past ten years, scientists have found that the types and amounts of bacteria in our intestines—the “microbiome”—can affect how the brain works, even influencing mood, social behavior, and learning. One bacteria that keeps coming up in this research is L. reuteri.

In animal studies, mice that lack gut bacteria often show social problems similar to those seen in ASD. When researchers give these mice L. reuteri by mouth, their social skills often get better. Scientists believe this happens because L. reuteri talks to the brain through the vagus nerve, a key line of communication between the gut and the brain. When L. reuteri is present, it seems to help the brain release more oxytocin—a hormone linked to bonding and social connection.

Oxytocin is sometimes called the “love hormone.” It plays a big role in how mammals, including humans, form relationships and respond to voices, especially in early life. Some studies in humans suggest that children with ASD may have lower levels of oxytocin, and that their gut bacteria are different from those of other children. But until now, most of these findings have come from small groups or animal models. There is little evidence from large, well-designed clinical studies in infants.

Previous patents and research have proposed using genetic markers or brain scans to predict ASD risk, but these methods are costly, need special equipment, or are not practical for routine screening in babies. Other research has looked at the overall mix of gut bacteria, but not at a single, easy-to-measure species like L. reuteri. There are also probiotics on the market, including L. reuteri strains, but none are approved or marketed specifically to reduce ASD risk or as part of an early diagnostic pathway.

This patent application builds on the latest science from both animal and human studies. It proposes that a lack of L. reuteri in early infancy may be a key “final common pathway” leading to problems with social development, regardless of the many possible genetic or environmental triggers for ASD. In other words, no matter the root cause, a low level of L. reuteri might be a warning sign that a baby is at high risk.

The invention goes further, suggesting that by measuring L. reuteri in stool samples from babies (using a sensitive method called quantitative PCR, or qPCR), doctors could spot at-risk infants before behaviors change. It also explores measuring markers like oxytocin in saliva, or using brainwave tests to check how babies respond to human voices. These ideas are supported by studies showing that typically developing babies respond strongly to their mother’s voice, while those later diagnosed with ASD often do not.

What makes this invention different from earlier work is the focus on a simple, practical, and objective lab test that could fit into real-world clinics. By zeroing in on L. reuteri, a bacterium known to be safe (found in breast milk and already given to infants in other settings), the approach could be widely adopted if proven effective.

Invention Description and Key Innovations

This patent application lays out a new, step-by-step method for assessing a baby’s risk of developing ASD. Let’s walk through the main ideas in plain language.

1. Measuring L. reuteri in Infants
The invention starts by collecting a stool sample from an infant. This can be done at home, following simple instructions. The sample is then tested in a lab to determine the amount of L. reuteri present. The method uses qPCR, which is a sensitive and specific way to detect even very low levels of bacteria. Special primers—short pieces of DNA unique to L. reuteri—are used, making the test reliable and accurate.

The test works for infants as young as one day old, up to about three years. This is important, as it covers the window before classic ASD symptoms typically appear. By comparing the amount of L. reuteri in the sample to a threshold (a level found in healthy, low-risk children), doctors can assess if a child is at higher risk.

2. Adding More Clues: Oxytocin and Brain Response
In some versions, the method also checks how a baby responds to human voices. This can be done by measuring oxytocin in saliva samples (before and after hearing a parent’s voice) or by recording the baby’s brainwaves (event-related potentials, or ERP) during listening tasks. Low oxytocin or weak brain responses to voice may add to the evidence of ASD risk.

3. Linking Test Results to Risk

The invention provides clear guidance: if a baby’s L. reuteri level is below the threshold, or if their response to voices is weak, they may be at higher risk for ASD. This can help parents and doctors decide whether to monitor the child more closely or start early interventions.

4. Early Intervention: Probiotics and Beyond
If a baby is found to have low L. reuteri, the patent proposes giving them L. reuteri as a supplement (by mouth). The strain used (ATCC PTA 6475) has a good safety record in infants and is already available as a probiotic. The idea is that restoring normal levels of this bacterium could help the baby’s brain develop healthy social circuits, possibly lowering the chance of developing ASD symptoms later.

The method also allows for follow-up testing after probiotic therapy—rechecking L. reuteri levels, oxytocin, or brain responses to see if things have improved. This approach makes the whole process dynamic: test, treat, and test again if needed.

5. A Ready-to-Use Kit
To make the process easy for clinics and families, the invention includes a kit containing everything needed to collect and test samples for L. reuteri. The kit provides the right reagents (for qPCR), written instructions, and even the special DNA primers for L. reuteri. Optional parts of the kit could include materials for measuring related markers like BH4, a chemical produced by L. reuteri, or for testing oxytocin.

6. Safety and Practicality
Importantly, the patent addresses safety. L. reuteri is a natural part of the human gut, especially in breastfed babies. It has been used in many studies with infants, with no serious side effects reported. Giving it as a supplement is much safer than many medicines. The test itself uses a stool sample—a non-invasive, low-stress option for babies and parents.

7. Tailoring to the Individual
The invention also leaves room for flexibility. If a child does not improve after taking L. reuteri, or if certain responses are still low, doctors could look for other causes, including genetic changes affecting oxytocin pathways. This could help guide which children might benefit from other treatments, like oxytocin nasal spray, or more targeted therapies.

8. Clinical Study Design
To prove the method works, the patent describes a large clinical study. High-risk babies (those with an older sibling with ASD) and low-risk babies are enrolled. Some get L. reuteri, some get a placebo, and all are followed until age two. The study checks how L. reuteri levels, oxytocin, and brain responses change over time, and whether these predict later ASD diagnosis. This careful design ensures that the method is tested in a real-world setting, with enough data to draw strong conclusions.

9. Statistical Rigor
All data is analyzed using robust, modern statistical methods. Differences in L. reuteri levels, oxytocin, and brain responses are tracked over time, and compared between groups. The analysis is designed to find out not just if there is a link, but how strong it is, and whether changes in L. reuteri lead to real improvements in social development.

10. Broad Impact
If successful, this invention could transform how ASD risk is managed. Instead of waiting for behaviors to emerge, doctors could use a simple stool test to spot high-risk babies and offer early support. This could reduce the lifelong burden of ASD for many families, and save billions in healthcare costs.

Conclusion

This patent application brings together new science, clever lab techniques, and a deep understanding of the needs of families and doctors. By focusing on L. reuteri, a safe and natural gut bacterium, it offers a practical, objective way to screen infants for ASD risk. It also lays out a path for early intervention—using probiotics—to possibly prevent or reduce social challenges before they appear.

The key strengths of this approach are its simplicity, safety, and grounding in solid science. By using stool samples and well-known lab tools, the method can be adopted widely, even in everyday pediatric clinics. The inclusion of follow-up testing and clear next steps gives doctors and parents a roadmap for action.

ASD is a complex and diverse condition, but by focusing on a “final common pathway” like L. reuteri deficiency, this invention could help bypass some of the mystery. If future studies confirm its value, this method could mark a true turning point in the early diagnosis and care of children at risk for autism.

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