E-Mail Scientists at the Walter Reed Army Institute for Research have shown that microRNA biomarkers related to Alzheimer's disease play a role in brain damage caused by traumatic brain injury. TBI or brain trauma results from blows to the head, leading to chronic disruption of the brain and a cascade of long-term health conditions. Patients who suffer from TBI are at much higher risk of developing neurodegenerative disease or dementia, particularly Alzheimer's disease. The mechanism behind this relationship remains understudied, making the development effective therapeutics challenging. MiRNAs are small pieces of genetic material that play a critical role in normal gene expression. Yet, studies have also linked abnormal miRNA levels, or dysregulation, to a range of diseases including neurodegenerative disorders and cell death after TBI, making them a subject of great interest to researchers who hope to use them as biomarkers and novel targets of drug therapies.