Ancient tooth DNA reveals the evolution of the "cold sore" herpes virus

Ancient DNA extracted from human teeth that lived long ago provides new information

In a recent study, researchers found and sequenced the genome

Christiana Scheib, an archaeological molecular biologist at the University of Tartu in Estonia, says this and other studies related to tooth extraction DNA are yielding surprising insights into

A breakthrough on the bone

Teeth are a treasure trove of ancient DNA because they protect biomolecules from degradation

In the process, they also classify

Ancient DNA traces the origins of the Black Death

Martin Sikora, a researcher in ancient genomics at the University of Copenhagen in Denmark, said recognizing that teeth are reservoirs of pathogen DNA opens up "a completely different kind of knowledge than we could have previously acquired"

Scheib said this genetic information provides researchers with molecular evidence to determine when and where

Studying ancient DNA could also help researchers understand the history of less deadly pathogens, such as oral herpes, which has infected about two-thirds of the world's population

Ancient teeth show that the Denisovan adventures go far beyond Siberia

Before that, she said, "no DNA of ancient herpes had been published at all

After sorting through dozens of remains, the researchers eventually found and extracted herpes DNA from the teeth of three people who died from an active infection, including a young woman who was buried outside

By evaluating genetic mutations that evolved in these four ancient genomes and comparing them to modern HSV-1 strains, the researchers deduced that they all shared a common ancestor that appeared about 5,000 years ago

Exactly what caused this new herpes virus to be more successful than the old herpes virus is unclear

The collapse of Aztec society was linked to a catastrophic outbreak of Salmonella

It may also spread as romantic kissing develops

Daniel Blanco-Melo, an evolutionary virologist at the University of Washington in Seattle, said that to fully unravel the history of herpes and other pathogens, older, more geographically diverse samples are needed, but the study is a good example

In theory, Sikora said, researchers could perform DNA sequencing on pathogens that infect older humans and animals, which could have lived 1 million years ago
.
This may give scientists insight into creatures that infected ancient human species such as Neanderthals and Denisovans
.
But technical limitations mean that researchers can currently only sequence genetic material from pathogens containing double-stranded DNA, ruling out many important RNA viruses, such as those that cause polio and measles
.

Still, Sikora says, ancient DNA provides a window
into the common history of humans and disease.
He added: "We are at the beginning
of a mature space in this area.
I expect that in the coming years, we will gain very exciting new insights
.
”