What Are Biomarkers?

Biomarkers are biological indicators—measurable signals in the body—that offer insight into what’s happening internally, often before any symptoms appear. In neurodegenerative diseases, they help reveal changes in the brain such as protein accumulation, inflammation, or neuron loss.

There are several key types of biomarkers:
Molecular biomarkers measure specific molecules found in biological samples such as blood or cerebrospinal fluid.
Imaging biomarkers use tools like MRI or PET scans to visualize brain structure or function.
Physiological biomarkers track changes in things like sleep, movement, or brain activity that may signal underlying neurodegeneration.

Among these, blood-based molecular biomarkers are one of the most exciting developments. Unlike spinal taps or brain scans, blood tests are low-cost, minimally invasive, and easy to repeat. While they are not yet used on their own to provide a diagnosis, they provide an accessible early warning system, prompting further testing when needed.

Think of them like a cholesterol test: not diagnostic on their own, but powerful in flagging risk and guiding next steps. In neurodegenerative diseases, where timing is critical, this early signal can make all the difference.

Why Biomarkers Matter

Biomarkers don’t just help identify disease, they help us understand brain health on a spectrum. Even in people with no symptoms or concerning results, biomarkers can reveal subtle shifts over time and offer a chance to optimize brain health before problems develop.

By tracking these biological signals—like levels of Amyloid beta 40 and 42, or phosphorylated tau 217 and 181—clinicians can personalize care in a way that’s proactive, not reactive. Some individuals may already fall within a healthy range, but even then, targeted lifestyle or therapeutic changes can help improve those markers and support long-term cognitive resilience.

This is where biomarkers become truly powerful: they enable individualized, data-driven care for anyone, at any stage. Whether someone is managing risk, trying to delay onset, or actively treating a diagnosis, biomarkers help measure progress and refine strategies over time.

Advances in Biomarker Research

At the Institute for Neurodegenerative Diseases, we’re actively working to make biomarkers even better—driving innovation to expand their impact, accuracy, and clinical usefulness.

Biomarker testing tends to focus on single indicators like a specific form of tau or amyloid. But neurodegenerative diseases are complex, and no one marker can capture the full picture. That’s why IND is developing multi-marker panels, combinations of blood-based biomarkers that work together to provide a more comprehensive and reliable view of brain health.

We’re also working to define clear reference ranges, so clinicians can interpret biomarker levels with confidence. Just like cholesterol has cutoffs that guide treatment, brain biomarkers need standardized benchmarks to show what’s normal, what’s changing, and when it’s time to intervene.

In parallel, our researchers are advancing test sensitivity and accuracy, ensuring that even subtle shifts in biology can be detected early and monitored over time. These improvements are making biomarker testing more practical and powerful, not just for identifying risk but for guiding treatment and prevention strategies.

This work is anchored by IND’s ongoing clinical research, including the Biorepository Study for Neurodegenerative Diseases. This long-term study is collecting and analyzing blood samples from over 100 individuals to validate emerging biomarkers and accelerate their translation into everyday clinical use.

Challenges and Future Directions

As biomarker science continues to advance, there are still important hurdles to overcome before it can be seamlessly integrated into everyday care.

Standardization and validation are top priorities. Biomarkers must be accurate across both symptomatic and asymptomatic individuals, and perform consistently across different labs, technologies, and patient populations. Variability due to age, genetics, or sample handling must be addressed to ensure reliable results.

Access and affordability remain major concerns. While blood tests are more scalable than brain scans, they still aren’t widely available or reimbursed. Expanding access isn’t just a scientific goal, it’s a moral imperative to ensure early detection tools benefit everyone, not just a few.

There are also ethical and regulatory challenges. As the field grows, it’s essential to safeguard patient data, ensure transparency, and put people before profits. Building trust will be just as important as building better tests.