http://weekly.ahram.org.eg/News/20676.aspx
Not out of Africa?
Recent DNA analysis apparently showing that the ancient Egyptians were more Levantine than African has created controversy among Egyptian archaeologists
Egyptian mummy
Early this week, scientists and researchers from the Max Planck Institute for the Science of Human History at the University of Tubingen in Germany revealed that the ancient Egyptians were genetically related to ancient Turkey and the Levant and not as African as had previously been thought.
The results were published in the journal Nature Communication after a DNA analysis on 151 Egyptian mummies from a period lasting from 1388 BC to 426 CE when Egypt become a province of the Roman Empire had been conducted.
The mummies came from an area named Abusir Al-Meleq, an ancient community in the middle of Egypt, and the DNA samples were extracted from the bones, teeth and soft tissues of the mummies.
Johannes Krause, a paleogeneticist from the University of Tubingen who made the study, told the US newspaper the Washington Post that the major finding was that "for 1,300 years, we see complete genetic continuity". Despite repeated conquests of Egypt by Alexander the Great, the ancient Greeks, Romans, Arabs and Assyrians, the ancient Egyptians showed little genetic change.
"The other big surprise," Krause said, "was that we didn't find much Sub-Saharan African ancestry."
Comparing of the results was done with modern Egyptians and Ethiopians, and the results showed that the ancient Egyptians were closely related to people who lived along the eastern Mediterranean coasts and that they also shared genetic material with residents of the Anatolian Peninsula at the time and Europe.
African genes were found in only 20 per cent of the material, and this was due to trade exchange.
In their paper, the researchers acknowledged that "all our genetic data were obtained from a single site in Middle Egypt and may not be representative for all of ancient Egypt." In the south of Egypt, the authors wrote, Sub-Saharan African influences may have been stronger.
The study has triggered anger among several Egyptian archaeologists who have questioned the results. Egyptologist Zahi Hawass described the studies as "hallucinations" and told Al-Ahram Weekly that they were not accurate for several reasons.
The mummies that were subjected to the DNA tests dated to the Graeco-Roman period when the mummification process was very poor, he said. They also belonged to people who came from Italy or to Greeks who lived in ancient Egypt and not to native ancient Egyptians.
"How can the ancient Egyptians be genetically from Europe," Hawass asked, adding that when the ancient Egyptians were busy building their civilisation Europe did not exist in civilisational terms.
"There is no scientific or archaeological evidence that could support such results," Hawass said, adding that the only discovery that scientists think could indicate the origin of the ancient Egyptians was the Naqad Necropolis discovered by archaeologist Flinders Petrie which houses a collection of tombs from the prehistoric period.
"The ancient Egyptians have Egyptian genes, which are not similar to African or Arab genes," Hawass said.
He said that recent studies were not the only ones to be published about the genes and the origins of the ancient Egyptians. Thirty years ago, an African clergyman claimed that the ancient Egyptians were Africans because both the pharaohs Ramses II and Tutankhamun had commissioned wooden statues painted black, he said.
The theory was discussed and disproved because all the walls of ancient Egyptian temples depict pharaohs fighting off enemies from Africa and Asia. A European institute had also conducted DNA analysis on samples from Tutankhamun and compared them with others from Europeans, and this had revealed only a 60 per cent similarity.
A piece from Tutankhamun's mummy had been sent to Europe for study after the discovery of the tomb in 1922 to investigate the reason for Tutankhamun's early death. The result revealed that the king had died from burns, which was "totally untrue", Hawass said.
Archaeologist Howard Carter had burned some parts of the mummy using a hot knife in order to remove the precious stones inserted in different parts of it. A burned part of the mummy had then been analysed, vitiating the results.
Yehia Zakaria Gad, professor of molecular genetics at the National Research Centre, the founder of the First Ancient DNA Lab in Egypt and a member of the Egyptian team put together to scan the mummies, told the Weekly that the scientific article published is another evidence against the scepticism of the long survival of DNA in Egyptian mummies. This scepticism was drawn from the failure to replicate the early studies, misconceptions based on papyrus of DNA decay rate [despite the radically different postmortem treatments of the human and animal bodies] and the circulating theories that the hot and humid tomb environment enhances the decay of DNA in buried mummies.
Gad noted that these theories were not substantiated by rigorous studies on the tomb temperatures or humidity levels. "On the contrary to these beliefs, my personal experience of working for extended hours down several tombs during mummy sampling sessions is that the underground temperatures and humidity were always within the comfortable range irrespective of the outside weather."
"This scepticism was adopted by a sector of the field scientists despite the results of several research groups, including ours, on human remains, ancient microbes and animal mummies like crocodiles and cats. Specifically, our team has presented data on the 18th Dynasty and Ramses III as well as the application of the most advanced technologies on Egyptian mummies," Gad asserted.
He added that the importance of the current paper is that it helps in lifting the roadblocks that were crippling the research on ancient DNA from Egyptian mummies.
On another level, he continued, there is no doubt that Egypt was a hub to the ancient world. "It is unfortunate that the published genomic data on ancient Egyptians is quite scarce. Egypt is known to occupy an important place in the history of mankind where it is hypothesised that the early man came from Africa and exited it through Egypt and its corridor to Asia [ie Sinai] and Europe."
Thus, Gad confirmed, the gene trends (or the DNA sequences that are transmitted from parents to their descendants) show a gradual shift and a continuum among all studied populations. Several studies have shown that contemporary Egyptians share with a higher percentage the gene sequences of Europeans rather than those of Sub-Saharan Africans.
"The presented data in this article shed some light on this issue although it focused largely on studying maternally inherited DNA of the mitochondria and only the nuclear DNA of three males," Gad told the Weekly. He opines that the effects of a foreign gene pool on that of a local Egyptian population will be gender-sensitive. For example, the impact of mobility of a human group, like a tribe having both male and female subjects, will be different from those of invading troops, which are mostly males.
Moreover, Gad explains, trying to draw major conclusions regarding the shifts in gene trends among Egyptians based on a limited study in a certain location seems to be over-speculation since this may not represent all ancient Egyptian population groups.
-- Sent from my Linux system.
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