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Feb 4

(Images: Leicester University/Rex Features)

Doubts remain that the Leicester body is Richard III

Hacked, sliced, stripped, slung over a horse and stabbed in the bottom. Tradition tells us that Richard III - the last Plantagenet king of England - met an especially bloody end in the battle of Bosworth Field on 22 August 1485. Now we may have a body to go with the legend.

Anticipation started building last year when an interesting skeleton was unearthed from beneath a car park in Leicester, UK. Today a team of researchers from the University of Leicester announced that, "beyond reasonable doubt", the body is that of Richard III. They draw on multiple strands of evidence to back their claim: as well as the expected wounds, the skeleton shows signs of scoliosis, a disease that curves the spine, which fits with accounts of the king being “hunchbacked”.

But the clincher - for the researchers, at least - is newly revealed DNA evidence from two of Richard’s living maternal descendants.

Michael Ibsen, a furniture-maker originally from London, and his distant cousin, who wishes to remain anonymous, were tracked down using genealogical records. Geneticist Turi King of the University of Leicester then matched traces of mitochondrial DNA extracted from the skeleton with samples taken from the purported relatives. Since Ibsen and his cousin are both the last of their lines, this could have been the last chance for such evidence to be obtained.

Mitochondrial DNA is passed down the maternal line and has 16,000 base pairs in total. Typically, you might expect to get 50 to 150 fragments from a 500-year-old skeleton, says Ian Barnes at Royal Holloway, University of London, who was not involved in the research. “You’d want to get sequences from lots of those fragments,” he says. “There’s a possibility of mitochondrial mutations arising in the line from Richard III.”

"It’s intriguing to be sure," says Mark Thomas at University College London. It is right that they used mitochondrial DNA based on the maternal line, he says, since genealogical evidence for the paternal lineage cannot be trusted.

But mitochondrial DNA is not especially good for pinpointing identity. “I could have the same mitochondrial DNA as Richard III and not be related to him,” says Thomas.

The researchers used the two living descendents to “triangulate” the DNA results. The evidence will rest on whether Ibsen and his cousin have sufficiently rare mtDNA to make it unlikely that they both match the dead king by chance.

They must also not be too closely related. If Richard III’s living descendants shared a common female ancestor even 150 years ago, their DNA could still be too close for the pair to count as distinct samples, says Thomas.

We’ll have to wait for the results to be published to know for sure, says Barnes.

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