Pompeii: the human genome of the victims sequenced for the first time

The researchers studied the remains of two individuals found in a building known as the Casa dell’Artigiano, a dwelling in the densely populated center of Pompeiiand distilled their DNA, according to a study published Thursday in Journal of Scientific Reports.

Pompeii was home to up to 20,000 people before it was destroyed by the eruption, visible from over 40 kilometers (25 miles) away. More than 2,000 people died as a direct result. The city was buried under a 23-foot-deep layer of ash and debris following the volcanic explosion, which preserved the ruins from the damaging effects of weather and climate. It has since become a popular tourist destination as well as a rich study site for archaeologists.

The structure, shape and length of both skeletons suggest that one set of remains belonged to a man between the ages of 35 and 40 when he died, while the other skeletal remains were from a 50-year-old woman.

While the scientists could obtain ancient DNA from both individuals, they were able to sequence the entire genome from the man’s remains only because there were gaps in the sequences extracted from the woman’s remains.

“Pompeii is one of the most unique and remarkable archaeological sites on the planet, and it is one of the reasons we know so much about the classical world. Being able to work and contribute to adding more knowledge about this unique place is incredible Gabriele Scorrano, assistant professor in the department of University of Copenhagen health and medical sciences and lead author of the study, he told CNN via email.

Pompeii is one of the most studied archaeological sites in the world, but obtaining detailed genetic information from the skeletal remains preserved in Pompeii had long eluded scientists.

Serena Viva, postdoctoral researcher at the University of Salento and lead author of the study, conducts a preliminary anthropological study of the male skeleton.

Prior to this latest study, only short stretches of mitochondrial DNA from human and animal remains from Pompeii had been sequenced, according to a press release announcing the study.

Scorrano said it may have been possible to successfully extract ancient DNA from their samples because pyroclastic materials – a boiling mixture of gas, lava and debris – discharged during the eruption may have protected the DNA from environmental factors, such as oxygen. in the atmosphere that led to decomposition.

“Individuals in Pompeii weren’t in direct contact with volcanic lava, but rather were enveloped in volcanic ash,” Scorrano said.

He said this created an oxygen-free environment, which helped preserve the DNA in the skeletal remains.

“One of the main factors of DNA degradation is oxygen (the other is water). The temperature works more as a catalyst, speeding up the process. Therefore, if there is a low level of oxygen present, there is a limit. the amount of DNA degradation that can take place, ”added Scorrano.

The analysis of the genome has highlighted the genetic diversity of the human population that lived on the Italian peninsula when Pompeii was destroyed almost 2000 years ago.

Scientists compared the DNA of human remains with that of 1,030 ancient and 471 individuals from Western Eurasia.

Their findings show that it shared similar DNA to modern central Italians and other people who lived in Italy during the Roman imperial age, which occurred from 27 BC to 476 AD.

Injuries on the male individual's lumbar vertebrae, which are the five bones between the rib cage and the pelvis, suggest that he suffered from tuberculosis before he died.

Further analyzes of the mitochondrial DNA of the male individual, which refers to his matrilineal ancestry, and of his Y chromosome, which reflects the male line, also revealed clusters of genes that are frequently found in Sardinian people, but not among others. people who resided in Italy during the Roman imperial age.

“It is significant because it shows that there is still a lot we don’t know about genetic diversity in the Roman Empire and how this affects modern Italians and other Mediterranean populations,” Scorrano said.

Scientists are sequencing the complete human genome for the first time

The researchers also linked the lesions found during the analysis of the male individual’s skeleton and DNA to mycobacterium, the type of bacterium linked to tuberculosis, suggesting that he suffered from this disease before his death.

“Participating in a study like this was a great privilege, Pompeii is a unique context from all points of view, the anthropological one allows you to study a human community involved in a natural disaster,” said Scorrano.