Science Illustrated Nov-Dec 2010
By the fall of 1922, English archaeologist Harward Carter had spent six years digging in Egypt’s Valley of Kings. He was losing hope that he would even find an undisturbed royal tomb – his ultimate goal – when his team encountered steps leading to a forgotten chamber. Although robbers had penetrated its outer rooms, the inner tomb, which held the burial room and treasury, was found untouched, a first for any Egyptian expedition. Behind a sealed wall, the sarcophagus of the haraoh Tutankhamun lay intact amid piles of precious grave goods destined to accompany him on his journey to the afterlife.
The artifacts provided historians with new clues to ancient Egypt’s power in the Mediterranean, its affluence, religious eliefs, politics and funerary traditions. Within weeks, the New York Times heralded Tutankhamun as “the most sensational Egyptological discovery of the century.” In the decades following the discovery, traveling museum exhibitions displayed the King Tut collections, further catapulting the pharaoh into the pubic eye.
Researchers have determined that Tutankhamun died in 1323 B.C. at the age of 19. only nine years after he ascended to the throne. Although pharaohs’ chambers were typically expansive and cut into the valley’s hills, Tut’s was small and built on the valley floor, suggesting that the chamber was hastily converted from one meant for a non-royal. Tut’s death, archaeologists reported, was unexpected, and his kingdom unprepared for his burial.
The evidence of Tut’s sudden death kicked off fervid speculation among modern scholars. Some took a suspicious hole in his skull as an indication that he had been murdered by a blow to the head. Others argued that Tutankhamen had been poisoned or had died in an accident.
In 2007, Egyptian and German scientists used improvements in DNA-collection techniques and radiology to try to solve the mystery. Zahi Hawass, the secretary-general of Egypt’s Supreme Council of Antiquities; Carsten Pusch, a molecular geneticist at the University of Tubingen’s Institute of Human Genetics; and their colleagues published the results of the two-year collaborative project this February in the Journal of the American Medical Association. The study was the first ever DNA analysis of royal mummies, and it offers insight into the life and death of Tutankhamun. Ancient Egypt’s best-known king rose to power on an inbread lineage, the researchers reported, and was weakened at a young age by physical deformities and disease.
Tutankhamun came to power in 1333 B.C. during Egypt’s 18th dynasty, which lasted from 1539 B.C. to 1292 B.C. It was one of the most powerful and prosperous periods in the civilization’s history. The country’s military and foreign-policy influence stretched into Asia and the mediterranean, and pharaos built monuments and temples at a rapid clip.
Sometimes in the last 100 years of the empire, the dynasty saw one of the biggest religious conflicts in Egyptians history. Just two years after ascending to the throne in 1353 B.C., the ruler Amenhotep IV unpended his civilization’s traditional beliefs, demoting Amun, the long standing king of the gods, below Aten, the sun-disk god. The pharaoh also declared himself the sole intermediary between Aten and the Egyptian people. The so-called “heretic pharaoh” officially changed his name to Akhenaten, abandoned the Egyptian capital of Thebes (modern day Luxor), and built a new ruling city named after himself about 200 miles south of Cairo, where Tell el-Amarna stands today. The shuttering of temples that funded local governments rendered political leaders powerless. When Akhenaten died in 1336 B.C., an interim ruler named Smenkhkare, about whome little is known, assumed the throne for two or three years.
Tutankhamun came to power next, Although he’s famous today, scholars believe the boy-ruler was not a pivotal figure in Egypt’s history. Only nine years old at the time of his ascension, Tut was essentially a fiturehead dominated by his chief advisers, Ay, a high priest, and Horemhed, a military general. Most likely at thir bidding, he restored Amun as the king of the gods, rebuilt the ruined temples, and reestablished Thebes as the capital city. Tut’s nine-year reign was notable only for decisions that he didn’t make himself.
Tut’s somewhat unremarkable reign, combined with the haste with which his tomb was assembled, left much about his heritage unknowable for decades. What was his father? Why was he eligible to rule? Several inscriptions dated to Tut’s monarchy identify Amenhotep III as his father, but the term can also be interpreted as “grandfather” or “ancestor”. Other inscriptions point to Akhenaten, and some scholars say that his father may have been Smenkhkare.
Several royal mummies unearthed in the Valley of the Kings that date to the time of Tutankhamun provide clues to his heritage. Until now, however, the mummies couldn’t be identified because their tombs were stripped of useful markers, such as artwork emblazed with personal histories, by grave robbers centuries earlier. But by leaving the bodies behind, the robbers left perhaps the best clue of all: DNA.
Geneticist Carsten Pusch had previously proved that DNA of sufficient quality and quantity to trace ancestry and disease could be obtained from ancient remains. In 2007, he and Hawass teamed up to determine how members of the royal family from the mid-to late-18th dynasty were related using a technique similar to a modern-day paternity test. Eleven mummies were selected for testing, all dating to roughly the period of Tutankhamun’s rule. In addition to Tut himself the mummies included two still born fetuses found in his tomb, assumed to be his daughters. Four of the 11 mummies had been identified prior to the study using evidence found in their tombs. Five additional older royal mummies from the period between 1550 B.C. and 1479 B.C. (approximately two centuries older than the Tut group) served as genetic and physiological control samples.
The team extracted DNA from 55 mummy bone biopsies. To reduce the risk of contamination by the researchers, the samples were sent to two seperate labs. Only results confirmed by both labs were used in the final analysis.
The researchers looked at micro-satellites, repeating sequences of DNA base pairs passed down from parents to children that can be used as a sort of genetic fingerprint. By matching one mummy’s dominant sequences with those of another male and female, the mummy’s parentage can be determined. Using this technique, the team compiled a five-generation family tree of Tutankhamun’s immediate lineage.
The results revealed that Tutankhamun’s father was a mummy known as KV55 (for King’s Valley, a grave number 55). KV55 was determined to be the some of Amenhotep III, whose mummy had previously been identified based on artifact inscriptions. Amenhotep III was known to be Akhenaten’s father, so the researchers concluded that KV55 was the remains of Akhenaten. Tutankhamun’s father, therefore, was Akhenaten, and his grandfather Amenhotop III. The father-son connection is supported by previous research, which found that KV55 and Tutankhamun shared the same blood type, as well as a slightly cleft palate and a characteristic overbite. CT scans of KV55’s bones, conducted in concert with the DNA analysis, indicated that he was between 35 and 45 years old when he dies, as evidenced by bone growth and damage; these results correspond to what historians know about Akhenaten.
The DNA also showed that Tutankhamun’s parents were brother and sister and that his wife was his half sister. Inbreeding, a common occurrence among ancient Egyptian royalty, kept royal wealth from passing to outsiders. And it was condiered the way of the gods, who were said to copulate with siblings. Pharaohs typically took additional wives or concubines, so it is not surprising that Nefertiti, Akhenaten’s legendary queen and senior wife, was not Tutankhamun’s mother. Akhenaten’s sister – Tut’s mother – was the mully called KV35YL (“YL” for Younger Lady).
A Frail Pharaoh
With Tutankhamen’s lineage settled, the researchers turned to the question of his mysterious death. His inbred parentage assured him the throne, but biologically it was no blessing. Inbreeding most likely contributed to several skeletal deformities, including a clubfoot and malformed toe bones, that showed up on Tut’s CT scans.
The scans also revealed non hereditary progressive bone loss in his left foot, possibly the result of Kohler disease or Freiberg-Kohler syndrome. These disorders temporarily shut off blood supply to foot bones, killing the tissue of the bone. As a result, Tutankhamen would have had paid and swelling in his left foot, beginning as early as the age of three, when the disease typically sets in. More than 100 walking sticks found in his tomb and several paintings depicting him with a cane and seated rather than standing on his chariot support the findings.
The researchers ruled out leprosy, plague or tuberculosis as culprits in Tut’s death. (And the hole in his skull, it was previously determined, resulted from the mummification process, not violence.) They did, however discover genes from the parasite Plasmodium falciparum, which causes the most severe form of malaria, in Tut’s bone marrow. Although it’s unlikely that malaria directly killed him – he had trace of multiple infections, indicating that he may have built up partial immunity to the disease – the combination of bone deformities and malaria could have caused an inflammatory, immuno-suppressive state. Pusch says. Combined with an already weakened immune system from his inbred lineage, the pharaoh’s health would have been compromised.
So what provided the death blow? CT scans taken in 2005, during one of Hawass’s previous projects, revealed a left leg fracture with no sign of healing. Hawass believes Tut broke his leg just before his death. With his immune system unable to fight off infection, the injury could have caused a bacterial overload in the bloodstream called speticemia, which can trigger multiple-organ failure and death in severe cases.
A New Beginning
Not everyone is satisfied with the new findings. A series of letters published in the June issue of JAMA contested the conclusions. Researchers from the Center of GeoGenetics at the Natural History Museum of Denmark questioned the reliability of the DNA samples, arguing that they might have degraded or been contaminated despite the precautions taken by Hawass’s team. A group from Arizona State University disputed the age ascribed to KV55, calling its identity as Akhenaten into question, and researchers from Stanford University Medical center argued against the CT evidence that Tutankhamun had a club left foot. Yet another group of scientists, from the Bernhard Nocht Institute of Tropical Medicine in Germany, believe that Tut’s foot malformations point to sickle-cell, nor Kohler disease.
Hawass’s team, however, remain confident in their analysis, and they have counterarguments for each objection. Improved CT technology for each objection. Improved CT technology, they say, allowed for more accurate determination of KV55’s age than previous scans, for example. As for the sickle-cell theory, which received significant press coverage, the researchers say they found no evidence of the hereditary disease among Tut’s newly identified relatives, which means Tut himself was unlikely to have had the disease.
Hawass and Pusch’s work had broad implications for Egyptology. The collaborative project offers a new pproach to deciphering history, one that merges the natural, life and cultural sciences with the humanities and medicine and ushers in an age of what they’ve dubbed molecular Egyptology. Time will tell if the emerging field can solve more of ancient Egypt’s remaining mysteries, among them finding the final resting place of Nefertiti.