February 4, 2013
In September I reported on the archaeological excavation in Leicester that had found a skeleton that could be the remains of King Richard 3rd. This morning the teams involved in the dig and the DNA analysis announced that the DNA tests had proven positive and the skeleton was indeed that of the king beyond any reasonable doubt.
The DNA test involved isolating mitochondrial DNA from the skeleton. This is DNA found inside the bodies cells in the mitochondria that are used to metabolize nutrients and provide energy. Unlike nuclear DNA this DNA is passed down from the mother only so to compare with the DNA of living people they had to find someone who shared a common female ancestor with King Richard where both lines of descendants are maternal. The final people in the line can be male and luckily one family with living males who could trace their lines was found. If this discovery had been made after their death it might have been impossible to make the DNA test.
The skeleton found also showed characteristics of a deformed spine and battle wounds that would have been fatal. This fits historical descriptions of Richard III and his final moments. These historical accounts had not been considered reliable in the past but the discovery of his remains confirms that they were perfectly accurate.
Richard III was the last of the Plantagenet monarchs of England from the 15th century so this discovery is very important for English history. His body will now be reinterred at Leicester cathedral.
If you are in the UK you can watch a documentary that followed the discovery on channel 4 this evening.
Update: I watched the program on channel 4 last night and was a little disappointed that much of the science was glossed over. For example, very little was said about the DNA other than it gave a match. It is a great pity that this was not covered by channel 4′s long running archaeology series “time team” who would have done a much better job of it.
The evidence that the skeleton found is indeed Richard III included
- The place of burial in the church matched expectations
- He had battle scars consistent with records of his final moments
- He had a curved spine as depicted in historical records (although doubted by his followers)
- His slight build was also consistent with accounts from people who knew him
- Carbon dating was spot on with an error range of a few decades
- Analysis indicated a high status diet that would have been available only to a few
- Mitochondrial DNA was a perfect match with authenticated ancestors through maternal lines
- The facial reconstruction produced a perfect match with his best portrait
The facial reconstruction was shown last night on TV and we be revealed online today.
It is notable that the whole project took place because of the insistence of one woman who was an amateur historian. She was refused the necessary grant of £10,000 but managed to raise it privately through the internet. When they first visited the car park there was a space marked with an R which they jokingly thought might mark the spot. It did!
September 15, 2012
Last week some archeologists from Leicester University made a breakthrough in their search for the resting place of King Richard III who died by a blow to the head at the battle of Bosworth in 1458 ending the war of the roses and the English reign of the Plantagenets. Richard III was the subject of a play by Shakespeare in which he was portrayed as a hunchback with a clubbed foot and a nasty character. Shakespeare may have been more than a little biased if he wanted to please the Tudor monarchy so it would be foolish to rely on his fiction. Finding Richard’s skeleton could confirm or refute some of what we think we know about him.
It is recorded that Richard was buried in a modest church in Leicester that was later destroyed. The archeologists believed they had located the ruins beneath a car park and sure enough they found a skeleton in a likely spot with clear signs of a fatal head wound and a deformed spine. Could this be the King? Taking a leaf out of the CERN guidebook to the press, Richard Taylor who lead the search said “We are not saying today that we have found King Richard III. What we are saying is that the search for Richard III has entered a new phase.”
To verify the owner of the bones they will resort to genetic evidence. DNA cn be extracted from bones thousands of years old so it should not be too hard to get a DNA profile from the skeleton, but whose DNA can it be compared with? The problem is that 20 generations have passed since Richard died, and he did not even have any direct descendants. You have 23 pairs of chromosomes that are shuffled with those of your spouse and passed on to your children. They will have 23 of your chromosomes but your grandchildren could have any number between 0 and 23 inherited from you. Most likely they will have 11 or 12, then your great grand children will have about 6, your great-great-grandchildren about three and so on. After six generations an offspring has up to 64 ancestors from which they inherit 46 chromosomes. There will be some from whom they have inherited no genes at all. After twenty generation any randomly chosen descendant is very unlikely to have any of your genes. The archeologists who found the bones claim to have identified a direct descendant of Richard’s sister. Strikes me that this is not a promising lead if they are plan to use nucleic DNA, (but see below).
One real possibility might be to exhume the bones of one of Richard’s close relatives whose grave is preserved. I am not sure if one can be found and might do some research on that later, but in any case it seems a little unlikely that permission to dig up the nobility will be granted on this basis.
Luckily there is an alternative. All men have a Y chromosome that is always passed from Father to son. This means that any direct descendant in a male line will always share at least that one chromosome. Richard had only one son who died at age 11 so we must look further back in his male line. His brothers shared his Y chromosome too but Richard himself is thought have killed two of his nephews to secure his own right to the throne, while Henry the VII beheaded the remaining nephew to avoid any arguments about his reign. Richard III had no uncles on his father’s side. In fact you need to go back to his great-great-grandfather King Edward III to find a direct male line to the present day who would share Richard’s Y chromosome. For the full list click here. This assumes that all lines are legitimate, possibly a strong assumption. Some living Plantagenets may be reluctant to allow their DNA to be tested in case they are found to be imposters. If a match can nevertheless be made, confirming the Y chromosome would only show that the bones belong to a Plantagenet. Carbon dating would give the rough date of death, enough to reduce the possibilities to just a few alternatives including Richard III.
One other avenue for genetic verification might be to isolate mitochondrial DNA from the bones. Mitochondrial DNA are shorter chains found in cells outside the nucleus and they are always passed from the mother. This could be compared with a direct female line, and female lines are more likely to be correctly documented unless there was a secret adoption. This line from his sister Ann of York may be the one they intend to use.
Update: According to New Scientist they do plan to look for mitochondrial DNA and have a descendant in the female line. There may be other female lines from his great grandmother Catherine Roet, but they are not well documented. Nucleic DNA could be harder to extract.