Remnants of ancient viral infections in the form of viral DNA sequences make up about 8% of the human genome. These are called human endogenous retroviruses (HERVs).
HERVs were transmitted to our primate ancestors millions of years ago and became incorporated into our genomes when the viruses inserted their DNA.
A new study found that 37 HERVs from one group (HML-2) are still actively transcribed or producing RNA in healthy human tissue samples across 54 donor tissues.
This suggests HERV genes are still functional in the genome, though their roles are not fully understood. Some may contribute to embryogenesis or protect against modern related viruses.
While HERV activation is associated with some diseases, their presence alone does not prove causation since they are also active in healthy tissues.
The discovery has implications for using HERVs as drug targets or disease biomarkers, and indicates more remains unknown about their functions in the human body.
Source: theconversation
