Ancient DNA just became older


Most science news in recent days have been focused on the Perseverance Mars Rover and its landing on Mars. However, that is not the only major science news in recent days. We have also had the publication of the news about million years old mammoth DNA being sequenced.

The Guardian reports on this: Million-year-old mammoth genomes set record for ancient DNA

Teeth from mammoths buried in the Siberian permafrost for more than a million years have led to the world’s oldest known DNA being sequenced, according to a study that shines a genetic searchlight on the deep past.

Researchers said the three teeth specimens, one roughly 800,000 years old and two more than a million years old, provided important insights into the giant ice age mammals, including into the ancient heritage of, specifically, the woolly mammoth.

This is really exciting, and will help create a more accurate picture of the lineage of mammoths, as well as expand the possible range for future sequencing. As the Guardian states:

Dalén said new technologies could allow the sequencing of even older DNA from remains found in the permafrost, which dates back 2.6m years.

For a good look behind the science, Patrícia Pečnerová, the Postdoc involved in the research, has written a great write-up: Pushing the limits with million-year-old DNA

The write-up gives an interesting and humorous look behind the scenes, as the starting paragraph clearly shows:

I had low expectations when we went into the lab to extract DNA from samples that based on geological evidence were 600 thousand to 1.2 million years old. At that point of my PhD, I already knew better than to put faith in high-risk/high-gain projects. And attempting to extract DNA older than has ever been done before topped the list of some pretty funky projects that I have been involved in, like trying to retrieve DNA from rocks from the ocean floor. Such efforts rarely yield results and end up in the invisible section of the CV where dreams go to die. My supervisor, Love Dalén, calls it character building.

The article is unfortunately behind a paywall at Nature: Million-year-old DNA sheds light on the genomic history of mammoths

Further reading: Million-year-old DNA provides a glimpse of mammoth evolution (news write-up in Nature)