Researchers
from the Francis Crick Institute and Liverpool John Moores University (LJMU)
have extracted and sequenced the oldest Egyptian DNA to date from an individual
who lived around 4,500 to 4,800 years ago, the age of the first pyramids, in
research published in Nature.
Forty years after Nobel Prize winner
Svante Pääbo's pioneering attempts to extract
ancient DNA from individuals from ancient Egypt, improvements in technology have now paved the way
for the breakthrough today, which is also the first whole genome (the entire
set of DNA in an individual) from ancient Egypt.
During this period of ancient Egyptian
history, archaeological evidence has suggested trade and cultural connections
existed with the Fertile Crescent—an area of West Asia encompassing modern-day
Iraq, Iran and Jordan, among other countries.
Researchers believed that objects and
imagery, like writing systems or pottery, were exchanged, but genetic evidence
has been limited due to warm temperatures preventing DNA preservation.
In this study, the research team
extracted DNA from the tooth of an individual buried in Nuwayrat, a village
265km south of Cairo, using this to sequence his genome.
The burial had been donated by the
Egyptian Antiquities Service, while under British rule, to the excavation
committee set up by John Garstang. It was initially housed at the Liverpool
Institute of Archaeology (which later became part of the University of
Liverpool) and then transferred to World Museum Liverpool.
The individual died at some point in the
overlap between two periods in Egyptian history, the Early Dynastic and Old
Kingdom periods, and had been buried in a ceramic pot in a tomb cut into the
hillside. His burial took place before artificial mummification was standard
practice, which may have helped to preserve his DNA.
By analyzing his genetic code, the researchers showed that most of his ancestry
mapped to ancient individuals who lived in North Africa. The remaining 20% of
his ancestry could be traced to ancient individuals who lived in the Fertile
Crescent, particularly an area called Mesopotamia (roughly modern-day Iraq).
This finding is genetic evidence that
people moved into Egypt and mixed with local populations at this time, which
was previously only visible in archaeological artifacts. However, the
researchers caution that many more individual genome sequences would be needed
to fully understand variation in ancestry in Egypt at the time.
By investigating chemical signals in his
teeth relating to diet and environment, the researchers showed that the
individual had likely grown up in Egypt.
They then used evidence from his
skeleton to estimate sex, age, height, and information on ancestry and
lifestyle. These signs suggested he could have worked as a potter or in a trade
requiring comparable movements, as his bones had muscle markings from sitting
for long periods with outstretched limbs.
Adeline Morez Jacobs, Visiting Research
Fellow and former Ph.D. student at Liverpool John Moores University, former
postdoctoral researcher at the Crick and first author, said, "Piecing
together all the clues from this individual's DNA, bones and teeth have allowed
us to build a comprehensive picture. We hope that future DNA samples from
ancient Egypt can expand on when precisely this movement from West Asia
started."
Linus
Girdland Flink, Lecturer in Ancient Biomolecules at the University of Aberdeen,
Visiting Researcher at LJMU and co-senior author, said, "This individual
has been on an extraordinary journey. He lived and died during a critical
period of change in ancient Egypt, and his skeleton was excavated in 1902 and
donated to World Museum Liverpool, where it then survived bombings during the
Blitz that destroyed most of the human remains in their collection.
"We've now been able to tell part
of the individual's story, finding that some of his ancestry came from the
Fertile Crescent, highlighting mixture between groups at this time."
Pontus Skoglund, Group Leader of the
Ancient Genomics Laboratory at the Crick and co-senior author, said,
"Forty years have passed since the early pioneering attempts to retrieve
DNA from mummies without successful sequencing of an ancient Egyptian genome.
"Ancient Egypt is a place of
extraordinary written history and archaeology, but challenging DNA preservation
has meant that no genomic record of ancestry in early Egypt has been available
for comparison.
"Building on this past research,
new and powerful genetic techniques have allowed us to cross these technical
boundaries and rule out contaminating DNA, providing the first genetic evidence for potential movements of people in Egypt at
this time."
Joel Irish, Professor of Anthropology
and Archaeology at Liverpool John Moores University and second author, said,
"The markings on the skeleton are clues to the individual's life and
lifestyle—his seat bones are expanded in size, his arms showed evidence of
extensive movement back and forth, and there's substantial arthritis in just
the right foot.
"Though circumstantial, these clues
point towards pottery, including the use of a pottery wheel, which arrived in
Egypt around the same time. That said, his higher-class burial is not expected
for a potter, who would not normally receive such treatment. Perhaps he was
exceptionally skilled or successful to advance his social status."
In future work, the research team hopes to build a bigger picture of migration and ancestry in collaboration with Egyptian researchers.
Source: Ancient Egyptian genome reveals North African roots and Fertile Crescent ancestry
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