The legacy of the Black Death, the family ties of the Neanderthals and other secrets of ancient DNA

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news about fascinating discoveries, scientific breakthroughs and more.

CNN
—

The rapidly expanding field of ancient DNA, formally known as paleogenetics, came of age in 2022, winning its pioneering scientist Svante Pääbo a Nobel Prize in medicine and physiology.

Pääbo, director of the Max Planck Institute for Evolutionary Anthropology in Germany, developed methods to recover, sequence and analyze ancient DNA from fossils, a feat that took decades. Researchers are using the techniques today to answer Fundamental questions about human history and the deep past of the planet.

Many of the discoveries overturn assumptions about prehistoric times. When Pääbo’s laboratory in Leipzig sequenced the first Neanderthal genome in 2010many were surprised to learn that our own species Homo sapiens met and had babies with Neanderthals.

Paleogenetics has continued Uncover amazing secrets of DNA hidden in bones, teeth, even dirt. Here are seven things we learned in this fascinating and emerging field in 2022.

The Black Death, the world’s most devastating outbreak of plague, killed half the population of medieval Europe in the space of seven years in the 14th century, changing the course of human history.

But research published in October he suggested that it was more than luck that determined who lived and who died. Centuries-old DNA analysis of victims and survivors of the Black Death identified key genetic differences that helped people survive the plague, according to a study published in the journal Nature.

That genetic legacy continues to shape the human immune system today, with genes that once conferred protection against plague now linked to increased vulnerability to autoimmune diseases such as Crohn’s disease and rheumatoid arthritis. Science magazine named the discovery one of its top breakthroughs of 2022.

Ancient DNA also shed light on the origins of the plague outbreak that caused the Black Death: detailed work in a study published in June.

Genetic material extracted from skeletons buried in a cemetery in Kyrgyzstan, where the tombstones referenced a mysterious pestilence, revealed the DNA of the plague bacterium — which scientists call Yersinia pestis — in three people who died in 1338, several years before the disease reached Europe in 1347.

discovered scientists a genetic snapshot of the oldest known family groupusing ancient DNA from Neanderthals who lived in the Chagyrskaya cave in southern Siberia in Russia.

The riverside hunting camp some 54,000 years ago was home to a close-knit community of about 20 Neanderthals, including a father and his teenage daughter, a young man who might have been a nephew or cousin, and an adult woman who was a second grade. relative, perhaps an aunt or grandmother.

The researchers also detected an unexpected pattern of female migration between the different strands of genetic ancestry.

The diversity of Y-chromosome DNA, which is inherited through the male line, was much lower than that of mitochondrial DNA, which is passed down from mothers. The study calculated that, in this group, two male individuals could expect to share an ancestor around 450 years before they lived. By contrast, the equivalent estimate for female individuals was around 4,350 years.

The researchers said the best explanation for this was that more than 60% of the Neanderthal women in the small Chagyrskaya group had migrated from another community. This social structure is common among today’s hunter-gatherer societies and is known as patrilocality.

Scientists in Denmark have detected the world’s oldest known DNA sequences in ice age sediments.

The Earth’s core, taken from northern Greenland, revealed that the polar region was once abundant with plant and animal life 2 million years ago. Mastodons, reindeer, geese, lemmings, and hares lived in an ecosystem that was a mix of temperate and arctic flora and fauna.

The genetic material on earth, dumped by all living organisms into the environment so long ago, tells a more complete story of prehistoric life than the fossil record.

This incomparable ancient ecosystem has no modern equivalentbut it could provide a genetic roadmap for how some species might adapt to the climate crisis.

In 2004, construction workers breaking ground on a shopping center in Norwich, England, discovered 17 bodies at the bottom of an 800-year-old well.

To understand more about how the six adults and 11 children whose remains were found there died, Recently, scientists were able to extract detailed genetic material preserved in bones thanks to advances in ancient DNA sequencing.

The genomes of six of the individuals showed that four of them were related, including three sisters, the youngest of whom was between 5 and 10 years old. Further analysis of the genetic material suggested that all six were “almost certainly” Ashkenazi Jews.

Judaism is primarily a shared religious and cultural identity, but as a result of a longstanding practice of intermarrying within the community, Ashkenazi Jewish groups often have a distinctive genetic ancestry that includes markers for some rare genetic disorders.

Researchers believe they all died during the anti-Semitic violence that ravaged the city, probably a February 1190 riot related to the Third Crusade, one of a series of religious wars supported by the Catholic Church.

Pompeii, preserved in volcanic ash after the eruption of Mount Vesuvius in AD 79. C., is one of the most intensely studied archaeological sites in the world, but obtaining detailed genetic information from the skeletal remains preserved in the city had long eluded scientists.

At the beginning of this year, The scientists said they had for the first time successfully sequenced the genome of a man who died after the eruption..

Prior to this latest study, only short stretches of mitochondrial DNA had been sequenced from human and animal remains at Pompeii.

It may have been possible to successfully extract ancient DNA from their samples because pyroclastic materials, a fiery mixture of gas, lava, and debris, discharged during the eruption could have shielded the DNA from environmental factors, such as oxygen in the atmosphere that led to breaking down

The information shed light on the man’s ancestry and health.

A majestic horse-like creature known as a kunga that lived 4,500 years ago was the first known hybrid animal, with parents from two different species, according to research published in January.

Descriptions and images in Mesopotamian art and texts portrayed a powerful animal that pulled war chariots into battle and royal vehicles in parades. The intact skeletons of the creatures were buried alongside high-status people of the time.

His true identity, however, long puzzled archaeologists. Domesticated horses did not arrive in the region, sometimes called the Fertile Crescent, until 4,000 years ago.

DNA sequencing of the animal’s skeleton revealed that it had a Syrian wild ass for a father and a donkey for a mother, and was likely deliberately bred by humans.

DNA sequence revealed the origin of some strange-looking human fossils – a thigh bone and part of a skull – found in a cave in southwestern China in 1989.

The primitive characteristics of the bones had puzzled scientists, who questioned which human species the fossils belonged to. Perhaps, they thought, they belonged to a hybrid population of extinct and modern humans or perhaps a previously unknown human species that existed alongside ours.

Chinese scientists recently extracted genetic material from the skull cap and found that the skull belonged to a female individual, who was likely a direct modern human ancestor, a member of Homo sapiens.

The researchers then compared the genome extracted from ancient DNA with the genomes of other people from around the world, both modern and ancient.

They discovered that the bones belonged to an individual who was deeply linked to East Asian Native American ancestry. Researchers believe that this group of people traveled to northern Siberia and then crossed the Bering Strait to become some of the first Americans.