New studies have uncovered a link between ancient viral DNA found in the human genome and the risk of developing two significant diseases that impact the central nervous system.
Recent research from King’s College London has discovered a connection between ancient viral DNA embedded in the human genome and the genetic risk for two major diseases affecting the central nervous system.
The research, carried out by academic teams from King’s College London and Northwell Health, concentrated on human endogenous retroviruses (HERVs)—the remnants of long-ago retroviral infections that have become integral parts of our DNA. Utilizing advanced genomic methods, the researchers identified distinct HERV expression patterns associated with multiple sclerosis and amyotrophic lateral sclerosis (ALS), which is commonly known as motor neurone disease. These results point to the idea that viral components in our DNA might be instrumental in the onset of these neurodegenerative conditions.
Neurodegenerative diseases are characterized by continued degeneration and loss of neurons, which leads to the decline of the nervous system’s structure and function. Multiple sclerosis is one of the most prevalent neurodegenerative diseases in young adults, affecting over 150,000 individuals in the UK who contend with this lifelong illness. In contrast, amyotrophic lateral sclerosis is rarer, with about 5,000 cases in the UK, and is linked to a more severe outlook.
The study, published in Brain, Behavior, and Immunity, represents a significant step forward in understanding the intricate genetic foundations of neurodegenerative diseases. While earlier investigations suggested a link between HERVs and these disorders, this research is one of the first to identify specific HERVs that correlate with disease risk.
“Our results provide strong evidence that particular viral sequences within our genome enhance the risk for neurodegenerative diseases,” remarked Dr. Rodrigo R. R. Duarte, co-lead author and Research Fellow at the Institute of Psychiatry, Psychology (IoPPN) at King’s College London. “These sequences are not mere remnants from ancient viral infections—they actively affect brain function in ways we are just starting to comprehend.”
The research team examined data from numerous brain samples to explore the link between HERV expression and genetic risk factors for four neurodegenerative conditions: Parkinson’s disease, Alzheimer’s disease, ALS, and multiple sclerosis. They uncovered a significant HERV signature on chromosome 12q14 (MER61_12q14.2) related to ALS, and another on chromosome 1p36 (ERVLE_1p36.32a) connected to multiple sclerosis. These viral sequences seem to play a role in homophilic cell adhesion—an important process for communication between brain cells. While no strong signatures were found for Alzheimer’s and Parkinson’s diseases, the researchers pointed out that larger investigations might reveal new connections in the future.
As the global impact of neurodegenerative diseases escalates—over 50 million individuals are currently affected worldwide, a figure expected to nearly triple by 2050—these findings pave the way for future research and the development of treatments. This revelation opens up new avenues for therapeutic interventions targeting HERVs. By gaining a clearer understanding of how these viral elements contribute to disease progression, researchers aim to develop innovative treatments that could lessen the effects of neurodegenerative disorders.
“This study, utilizing extensive genetic datasets and a novel analysis pipeline, effectively identifies which specific HERVs are critical in heightening the risk for neurodegenerative diseases,” said Dr. Timothy R. Powell, co-lead author and Senior Lecturer in Translational Genetics & Neuroscience at King’s IoPPN. “We now need to further investigate how these HERVs affect brain function and whether targeting them could present new therapeutic possibilities.”
The research was partially funded by the National Institute for Health and Care (NIHR) Maudsley Biomedical Research Centre, the National Institutes of Health (NIH), and The Psychiatry Research Trust.
