New research led by King’s College London (KCL) has uncovered thousands of DNA sequences derived from ancient viral infections expressed in the brain.
Among these, some DNA sequences contribute to mental health disorders such as schizophrenia, bipolar disorder, and depression.
Approximately 8% of our genome comprises sequences known as human endogenous retroviruses (HERV), which are remnants of viral infections that our ancestors experienced hundreds of thousands of years ago. Until recently, these “fossilized viruses” were thought to be merely junk DNA, lacking any significant function in the body. However, advancements in genomic research have shed light on their expression and function.
Ancient viral DNA in the human genome may influence the brain and the risk of certain mental disorders. (Photo: AI).
The authors analyzed data from large-scale genetic studies involving tens of thousands of individuals with and without mental health issues, as well as brain analysis results from 800 donated bodies. In total, five strong HERV expression signatures related to mental disorders were identified, each increasing the risk of one or two of the aforementioned mental health conditions.
According to the research team, a better understanding of these ancient viruses and how the associated DNA affects mental health has the potential to revolutionize studies in this field, leading to new methods for treating or diagnosing some complex forms of mental disorders.
