Log in

No account? Create an account
19 February 2010 @ 11:12 am
Hawass et al "Ancestry and Pathology in King Tutankhamun's Family" JAMA. 2010;303(7):638-647  
Because of J's obsession with ancient Egypt he follows the news of what's going on with the archaeology etc. And the big news this week was the publication of a paper which has done a genetic and anatomical analysis of Tutankhamun's mummy and those of several close relatives. The genetic stuff is entirely new, I believe - they have extracted DNA from the bones of the mummies & done genetic fingerprinting on it to look at the relationships between the people. The anatomical analysis is building on work that's gone before but using up-to-date methods etc, and again comparing Tutankhamun with his relatives to back up the relationships. As well as this they looked at evidence for diseases that you might expect to be present at that time & place, such as malaria.

Tutankhamun's immediate family are interesting not just because Tutankhamun's tomb was found "recently" and was intact when discovered. Tutankhamun was Pharaoh towards the end of the 18th Dynasty, a dynasty that ruled Egypt from c.1550BC to c.1295BC at the start of the New Kingdom period. The Pharaohs before him are known to be Amenhotep III, Akhenaten (initially known as Amenhotep IV), Smenkhare (a very enigmatic figure) then Tutankhamun. Akhenaten has attracted a lot of interest because during his reign he changed the religion of Egypt from a polytheistic one where the priests were the intermediaries with the gods to a monotheistic one where the Pharaoh was the only intermediary, all blessings flowed through him. He also moved the capital of Egypt from Thebes (where the great temples to Amun were) to Amarna where he constructed a new city with only temples to the Aten, his one god. This new religion & capital did not long survive Akhenaten - during Tutankhamun's reign the old ways were gradually reinstated and the capital moved back to Thebes.

Because of the religious changes Akhenaten, Smenkhare & Tutankhamun were fairly thoroughly removed from the historical record of the Egyptian people - some things survive, particularly at Amarna and in Tutankhamun's tomb, but their names are generally not in the King Lists of later Pharaohs or other documents. This means that things like the family relationships between them are not well documented. What is known is that Amenhotep III was married to Tiye, the daughter of Thuya and Yuya. Akhenaten is attested as their son. After that the relationships are more murky - was Tutankhamun a younger brother of Akhenaten? or his son? if his son, then by which wife? I think it's accepted that he's not the son of Nefertiti (Akhenaten's senior wife) but there are multiple other candidates. And who Smenkhare is and if he really existed is even more obscured - one theory is even that this could be a name (and male persona) that Nefertiti took to be Pharaoh after Akhenaten's death, other than that he could be a younger brother of Akhenaten or an older brother of Tutankhamun (and both of them sons of Akhenaten). Or he may not exist, he's mentioned so rarely that this might be misunderstanding of the texts available.

And there is a lot of speculation around Tutankhamun's state of health & cause of death. The art style of the Amarna era is odd - the royal family are represented with odd looking bodies, which has lead to speculation that they had various genetic disorders. And Tutankhamun died young (age 19), so was he ill? was he murdered? was it an accident?

So this paper presents three strands of evidence to look at all these questions. First they present genetic data on 11 mummies, including Tutankhamun and putative members of his immediate family, and use these to construct a 5 generation tree of relationships. This confirms the identity of some of mummies that were less well attested (and some previously totally unidentified), and puts Tutankhamun into context with his predecessor Pharaohs. He is shown to be the grandchild of Amenhotep III and Tiye, via two of their children - his parents were full siblings. Because of the existence in the historical record of Smenkhare it isn't really possible to say if Akhenaten is his father or not (although the paper states that in their opinion this is most plausible). The two fetuses found buried in Tutankhamun's tomb may be his daughters (rather than ceremonial offerings), but the identity of their mother isn't clear. The previously well identified mummies were Tutankhamun, Thuya and Yuya. It is now possible to be sure that the mummy of Amenhotep III is indeed correctly identified, and a previously unidentified mummy (known as K35EL) is his wife Tiye. Mummy KV55 may be Akhenaten (tho may also be Smenkhare or a different son of Amenhotep III as I note above), and KV35YL is Tutankhamun's mother and a full sibling of his father.

They then present an anatomical examination of those same mummies and dismiss any possibility of a diagnosis of a feminising genetic disorder, but show that clubfeet and cleft palates (amongst other things) ran in the family - unsurprising in some ways due to the level of inbreeding that both the historic record and the genetic analysis demonstrate.

And finally they look for evidence of a selection of diseases including Black Death, tuberculosis, leprosy, malaria. The only one present was malaria, with both Tutankhamun and his great-grandparents showing evidence of multiple infections with the parasite. They then speculate that Tutankhamun's death was really due to a multitude of things which then overwhelmed him - he was weak due to his congenital defects and repeated malaria infections, then a severe fracture to his leg would combine with those to lead to his death.

I pretty much have to take the anatomical data, and the egyptological discussion, on faith - I have insufficient knowledge in either of those fields to examine the data critically. The genetic analysis on the other hand is closer to my own field, so I can poke at it with a more professional & critical eye. Though you should bear in mind that I'm 5 years out of date and this wasn't quite my field when I was current. So before I go through the actual data, here's some thoughts on the methods/presentation.

They don't discuss the details of the extraction of the DNA from the bones of the mummies - they do however cite 4 papers (only 2 of which have overlapping authors with this paper) for the method they use, so I'm inclined to think (without reading those papers) that this is a known and tried method in the field of ancient DNA extraction.

They use commercially available kits to do the genetic fingerprinting, from a quick glance through the company's website they're used for more modern forensic applications too. I was, though, concerned that although they use 16 markers on the Y-chromosome analysis they only use 8 markers for the autosomal DNA (the rest of the DNA in the nucleus that is not sex chromosomes). The kit seemed to allow you to test more markers than that - but they don't mention why only 8. Was it that they had good data for those 8? or is this an accepted practice? (as I said, this isn't quite my field). Some note of that might have been nice.

They did analysis on 30 samples for each mummy, taken from different biopsies - it might've been nice to have seen a figure with the biopsy locations marked on it (in the supplemental data perhaps). And it would've been nice to see the numbers - the data given is noted as the "majority", but I think I would've liked to see the actual figures. It makes a difference if something came up in 16 of the samples or in 29 of the samples.

I would also have liked to see some controls! In the Y-chromosome analysis they do compare the three male mummies with another unrelated one. But in the bulk of the data they don't show the control data. It's not even clear if it's been done, although there is a line in the methods section about using 4 mummies from earlier in the 18th dynasty (not just royal family mummies) as a genetic control group. I would have liked to see this data (in the supplemental data again, maybe, not the main paper). They do, however, make it clear that everyone involved in the handling of the DNA was also analysed, and they state none of them had the same profile. It's unlikely anyone who handled the mummies prior to this study could have contaminated the data as the sample were taken from within the bone.

The mummies tested were:

  • Thuya (female)

  • Yuya (male)

  • Amenhotep III (almost certainly identified, but less sure than other named ones, male)

  • KV55 (an unknown male mummy thought to be maybe Akhenaten)

  • KV35EL (an unknown older female mummy)

  • KV35YL (an unknown younger female mummy)

  • Tutankhamun

  • Fetus 1 (from Tutankhamun's tomb, female)

  • Fetus 2 (from Tutankhamun's tomb, female)

  • KV21A (unknown female)

  • KV21B (unknown female)

The last 4 have very patchy data and this means it's very hard to draw any conclusions about them and their relationships.

The Y-chromosome analysis data isn't shown in a table or figure, but is just stated in the text. The three male mummies tested (Amenhotep III, KV55, Tutankhamun) share the same profile, so are in the same paternal line. You can't draw any other conclusions about precise relationships from that. They also didn't match modern people involved in the work, didn't match an older mummy thought to be unrelated, and no Y chromosomes were found in mummies thought to be female (a good cross check, and confirms the sex of them).

The fingerprinting they've done is short tandem repeat (STR) analysis - there are sections of DNA that are repeats of short sequences. It doesn't appear to do anything, and as a result these regions mutate more than functional sections of the genome, so can be used to trace familial relationships (unless of course you get a mutation right between two generations of the family you're looking at, but that is still a rare occurrence). For any given marker what they do is look at how many repeats the sample has - there will be 2 numbers of repeats, as chromosomes come in pairs. Brief explanation - the DNA in a person is organised into 46 chromosomes, 22 pairs of non-sex chromosomes normally known by numbers and 2 sex chromosomes (XX for women, XY for men). You inherit one of each pair of chromosomes from your father and one from your mother, and this is randomly organised. So if your mother's chromosomes are labelled A & B, and your Dad's are C & D, you could inherit chromosome 1 as A (from your mother) & C (from your father), chromosome 2 as A&D, chromosome 3 as B&D, chromosome 4 as A&D and so on; a full sibling of yours would get a different random selection, ie 1 B&D, 2 A&D, 3 B&C, 4 A&C. And importantly you MUST get one in each pair from each parent, you'll never have 1 A&B for instance.

So with the STR analysis you get a bunch of numbers for repeats of the short section for each marker, and you use markers spread across the chromosomes so that they are independently inherited. To look at one of the markers for Tutankhamun's family (a marker called FGA), Tutankhamun has 23 repeats on both chromosomes. Amenhotep III has 23/31, KV35EL (Tiye) has 20/26. So Tutankhamun cannot be the child of those two people - where would he get the second 23 from? KV55 has 20/23 - so you see he can be son of Amenhotep III/Tiye, and KV35YL has 20/23 as well (so she can be a daughter). And Tutankhamun can be the son of KV55/KV35YL because he can get one 23 from each of them.

Basically you do this sort of comparison across all the markers you look at - 8 in this case. And calculate probabilities for each trio (mother/father/child), they say 99.73% is the accepted standard for "practical proving" the relationship. The data they have in excess of this figure in all cases (tho as I said above I would've liked to see n numbers for the samples, and possibly more markers) so seems very solid.

The data shows:

KV35EL is the daughter of Thuya and Yuya.

KV35EL and Amenhotep III are the parents of KV55 and KV35YL.

KV55 and KV35YL are the parents of Tutankhamun.

Taking these three together with the historical record allows definite identification of KV35EL as Tiye (daughter of Thuya and Yuya known to have married Amenhotep III), and solidifies the identification of Amenhotep III's mummy.

They also state that they think KV55 is most plausibly Akhenaten - but just seem to dismiss Smenkhare out of hand, and I'm not sure the data support that. If KV55 is indeed Akhenaten, then KV35YL being a full sibling is interesting - why's she not the senior wife, being higher status than Nefertiti (who is not King's Daughter in the historical record, so not KV35YL)?

They do speculate on the data from the fetuses, that it isn't ruled out that they are daughters of Tutankhamun, and possibly KV21A but the data is so patchy that no firm conclusions can be drawn (and indeed they don't try to).

Dear lord that got long :)
Current Mood: pensiveinterested
Current Music: ABBA "ABBA Gold" then ABBA "More ABBA Gold"
John: thoughtfuljarel on February 19th, 2010 12:04 pm (UTC)
Thanks for writing all this out. It definitely makes it all a lot clearer to people like me :)
Margaretpling on February 20th, 2010 11:52 am (UTC)
ann_hk on February 19th, 2010 12:21 pm (UTC)
*seconds the above comment*

Margaretpling on February 20th, 2010 11:53 am (UTC)
Thanks;) Glad it's been interesting & useful to people!
Robdreema on February 19th, 2010 04:50 pm (UTC)
thirded, a lot of it's completely over my head, but it's very interesting
Margaretpling on February 20th, 2010 11:52 am (UTC)

If there's any specific you found confusing, let me know & I'll try and clarify it :)
Jonbigme on February 19th, 2010 04:53 pm (UTC)
That was really interesting. :)
Margaretpling on February 20th, 2010 11:50 am (UTC)
ext_225533 on February 19th, 2010 07:03 pm (UTC)
News from the Valley of the Kings
J reads my blog and suggested I read your article. I'm glad he did! I've quoted it on my blog so you may find a few of my readers popping over here to read what you have written. So far it's the only decent assessment of the paper I have found.

Many thanks
Margaretpling on February 20th, 2010 11:49 am (UTC)
Re: News from the Valley of the Kings
Thanks for the link (& for the compliments!) :)
jimreevejimreeve on February 19th, 2010 07:59 pm (UTC)
Yes, thanks VERY much for such a concise and helpful explanation - I've been trying to find something like this since the presscon...! Nice to see someone looking at the evidence rationally, if I might say so! :)
Margaretpling on February 20th, 2010 11:50 am (UTC)
Thanks! :) Glad it's useful & interesting to people!
(Anonymous) on February 19th, 2010 08:01 pm (UTC)
How about ages of that mummies? How many years has lived KV55? If something changes in this matter?
Margaretpling on February 19th, 2010 08:45 pm (UTC)
Re: Ages!
The ages of the various mummies would be based on the anatomical evidence, which I'm afraid is outside my area of knowledge, so I can only say what is said in the paper but not give any judgement on it. However, what is said in the paper is actually very little. And in particular, the age of KV55 is unfortunately not discussed at length - in the main paper there are a couple of mentions of their belief that KV55 was 35-45 at death and that this is different from earlier interpretations. In the supplementary data there is again only one mention of this revised age-at-death estimate, but no evidence is given and there is no discussion of this.
Re: Ages! - (Anonymous) on February 19th, 2010 10:26 pm (UTC) (Expand)
Re: Ages! - pling on February 20th, 2010 12:00 pm (UTC) (Expand)
Re: Ages! - (Anonymous) on February 20th, 2010 02:43 pm (UTC) (Expand)
Re: Ages! - pling on February 20th, 2010 02:56 pm (UTC) (Expand)
Re: Ages! - (Anonymous) on February 20th, 2010 04:02 pm (UTC) (Expand)
Re: Ages! - pling on February 21st, 2010 02:18 pm (UTC) (Expand)
Re: Ages! - (Anonymous) on February 21st, 2010 02:43 pm (UTC) (Expand)
(Anonymous) on February 20th, 2010 11:52 pm (UTC)
He Loved His Mother
So Akhenaten's father and mother were sister and brother. and Akhenaten loved his mother and she had Tut. Isn't this close to what Velikovsky speculated?
Margaretpling on February 21st, 2010 02:19 pm (UTC)
Re: He Loved His Mother
There is nothing in this paper to suggest that Akhenaten's parents were brother and sister (Tutankhamun's parents were, Amenhotep III and Tiye were not). There is also nothing suggesting Akhenaten or any of the male mummies tested had offspring with their mother.
(Anonymous) on February 21st, 2010 12:13 am (UTC)
velikovskey and oedipus
a good read from his book on aknaton3 aka oedipus might solve this dna riddle . akhnaton married more than once . he did marry his own mother a persian .any other person out there familiar with these ideas? the dates of his time are most definetly wrong. have fun with this riddle
Margaretpling on February 21st, 2010 02:19 pm (UTC)
Re: velikovskey and oedipus
There is nothing in this paper suggesting that Akhenaten had offspring with his mother.
ext_225636 on February 21st, 2010 03:02 am (UTC)
Very interesting breakdown of the report. That Tut's mother and father would turn out to be brother and sister really introduces a new woman to the Amarna royal family and if we are to assume that the Kv 55 individual is Akhenaten than the Kv 35YL may be his sister Sitamen or Isis.

Both women had titles as "King's wife" though neither bore the title of "Mother of the king". There are two other daughters of Amenhotep III including princess' Henut-Taneb and Nebetah though these two women are only known as king's daughters. Beketaten was probably too young.

If the remains from Kv 55 is Akhenaten than the name of Tutankhamen's mother is likely one of the above?

Margaretpling on February 21st, 2010 02:31 pm (UTC)
Re: Jama
In the supplemental data part of the paper they speculate on which sisters of Akhenaten are possibilities, here's the relevant sentences:

"The allele constellations in all short tandem repeat markers tested indicate that the KV35 Younger Lady is a full-sister of the KV55 mummy, and is unlikely to be Nefertiti or Kiya, neither of whom is attested as a daughter of Amenhotep III. This leaves Nebetiah and Beketaten, daughters of Amenhotep III not known to have married their father and who therefore might have married their brother, as the most likely candidates for the KV35 Younger Lady."

I'm not sure why only those two are considered - would having married Amenhotep III really rule out marrying Akhenaten subsequently? But as I said in my post, I'm really just taking everything they say about the egyptology on faith, I don't know enough about it to do otherwise :)
Re: Jama - (Anonymous) on February 21st, 2010 03:14 pm (UTC) (Expand)
Re: Jama - (Anonymous) on February 21st, 2010 05:47 pm (UTC) (Expand)
Re: Jama - pling on February 21st, 2010 07:20 pm (UTC) (Expand)
As relevant as Tacitustabula_x_rasa on February 21st, 2010 11:01 pm (UTC)
Hi- I got here in a very roundabout way, but I wanted to thank you for this analysis. I do Egyptology and forensics, but know only the basics about genetics. This is a very helpful and clear analysis!

Would you mind if I linked other people to this post?
Margaretpling on February 21st, 2010 11:04 pm (UTC)
Thanks, glad it's helpful :)

Link away, it's fine by me!
99.9999..... - (Anonymous) on February 22nd, 2010 09:18 am (UTC) (Expand)
Re: 99.9999..... - pling on February 22nd, 2010 02:00 pm (UTC) (Expand)
(Anonymous) on February 22nd, 2010 02:15 am (UTC)
U Copenhagen full genome sequence of 4000 yo Greenlander
About a week before you published this comment, a group at the University of Copenhagen reported in *Nature* on the reconstruction of the nuclear genome of a 4000 year old Inuk.

Morten Rasmussen et al. *Ancient human genome sequence of an extinct Palaeo-Eskimo* Nature 463, 757-762 (11 February 2010)

The article comments suggest that sequencing and analysis now takes months.

Any comments relative to the JAMA article?

Mike (near the Berkeley in California :))
Margaretpling on February 22nd, 2010 08:58 am (UTC)
Re: U Copenhagen full genome sequence of 4000 yo Greenlander
I've not read that paper, interesting to hear there are reports of successful DNA extraction & sequencing from even older bodies than these mummies. Although, of course, the preservation of the body is likely to have been totally different!
Re: U Copenhagen full genome sequence of 4000 yo Greenlander - (Anonymous) on February 25th, 2010 05:52 am (UTC) (Expand)
Re: U Copenhagen full genome sequence of 4000 yo Greenlander - (Anonymous) on February 24th, 2010 10:41 am (UTC) (Expand)
Re: U Copenhagen full genome sequence of 4000 yo Greenlander - (Anonymous) on February 25th, 2010 06:05 am (UTC) (Expand)
Re: U Copenhagen full genome sequence of 4000 yo Greenlander - (Anonymous) on February 25th, 2010 01:47 pm (UTC) (Expand)
ext_225764 on February 22nd, 2010 02:07 pm (UTC)
thank you so much for that, it really helps. I have posted a link to my blog Luxor News so expect a few more visitors. Regards Jane Akshar
Margaretpling on February 22nd, 2010 02:12 pm (UTC)
Glad to hear it's been useful! And thanks for the link :)