human endogenous retrovirus

virus group

Also known as: HERV

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Last updated

July 21, 2026

Quick Summary

Human endogenous retroviruses (HERVs) are remnants of ancient viral genetic material integrated into the human genome over evolutionary time. These "fossil" viruses, similar to extant retroviruses, are passed down through generations and constitute a significant portion of human DNA, estimated between 1 to 5 percent.1

Retroviruses, in general, carry their genetic information in the form of RNA and use an enzyme called reverse transcriptase to convert RNA into DNA. This allows their genetic material to become permanently integrated into the host cell's DNA. While HERVs are not typically infectious, they are thought to have influenced human genome evolution and have been implicated in certain diseases, such as multiple sclerosis.1

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retrovirus
Human ERVs (HERVs) have become distributed within human DNA over the course of evolution. They are passed from one generation to the next and make up an estimated 1 to nearly 5 percent of the human genome. HERVs are suspected of having influenced the evolution…
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Human ERVs (HERVs) have become distributed within human DNA over the course of evolution. They are passed from one generation to the next and make up an estimated 1 to nearly 5 percent of the human genome. HERVs are suspected of having influenced the evolution…
Read More