murreyandblue

A great WordPress.com site

Archive for the tag “haplogroups”

Richard III’s Prehistoric Foremother?

Recently I came across this fascinating blogpost by an archaeologist called Katharina, who was working on a Bronze Age burial site in Austria. The skeletons her team excavated have recently been DNA tested–and one of them carried the maternal haplogroup J1c2, which is part of the group to which Richard belonged.

Richard’s Bronze Age foremother?

Now there are differences in their DNA sequences; Richard has a rare mutation, making his exact group J1c2c3. So far, only about a dozen people from all worldwide testing sites have been found to carry this exact mutation. None as far as I know, have been found in continental Europe, so it looks as if the rare mutation occurred recently in his maternal line–either with Cecily Neville, his mother, Joan Beaufort, grandmother, Katherine Swynford, his great-grandmother, or Katherine’s mother, who was a migrant to England.

Haplogroup J, called ‘Jasmine’ by geneticist Bryan Sykes, is thought to be one of the last female haplogroups to enter Europe, first appearing in the Near East around Syria. It is a ‘sister’ to Mtdna haplogroup T, with both  groups having split off from  a foremother carrying the Haplogroup JT, which is not commonly found in Europe but still can be  found in the Near and Middle East. (I am Haplogroup T2b4 ,’Tara’, by the way, so part of the ‘sister’ group.) J and T are both considered, in particular,  hallmarks of the Neolithic revolution (agriculture)  in Europe and maybe even associated with the spread of Indo-European languages, although there were probably some earlier people with these haplogroup in the Mesolithic as well.  Today J and T are considered mid-size DNA groups, with about 12% of Europeans carrying some form of J and 9% carrying T.

All the people with haplogroup J will share a common maternal ancestor with Richard at some point…but it might be well be a 100 generations ago or even earlier! Obviously there are different clades of each haplogroup, each with different mutations, which show where the groups split and diversified, and hence some people with MTdna J will be closer  matches to Richard than others, the closest being those who have that elusive ‘3’, who all seem to come from Richard’s close family. (I myself am in the same maternal group as the last Tsar of Russia but my mutations are quite different to his; I’m more closely related to the outlaw Jesse James! And Ozzy Osborne! Still, they are all my relatives on some kind of  remote level, though!)

It’s quite fascinating to be able to look into the deepest past and see where we all came from, and how interrelated we really all are.

 

mtDNA-J-map

Richard III, snooker and probability

One thing of which we can be certain is that Richard III never played snooker. It was not invesnookernted until 1875 in Jabalpur by a Colonel Chamberlain (1). Nevertheless, it is an excellent vehicle for demonstrating the laws of probability with particular reference to the descent of the Plantagenet Y-chromosome from Edward III.

Imagine that you have walked into a snooker club where a member lends you four white balls and fifteen reds, the white balls obviously from more than one set, but in a drawstring bag. The cue balls represent the paternal links from Edward III to Richard III and the reds represent the descent from Edward III to Henry, 5th Duke of Beaufort (2). We already know that the 5th Duke’s living putative descendants have a different Y-haplogroup to Richard III, indicating that there is at least one “false paternity event” in one or both lines, but “Somerset 3” has a different Y-chromosome to his putative cousins, showing that another such has occurred at some time since 1760.

The bag is now held towards you and you are invited to insert your hand and withdraw a ball but you cannot discern its colour until you are holding it outside the bag – we are assuming randomness a priori. The probability of one random ball being red is 15/19 or approximately 79%. If you withdrew two balls, the probability of both being red is 15×14/19×18 or about 61%. The probability of three balls all being red is 15x14x13/19x18x17 or about 47%.

The probability of any paternal link in these chains being false is the same as stated above. We only know that there is one such event and it is 79% likely to have been in the descent to the 5th Duke but 21% to Richard. We cannot yet assume there to be more than one broken link in either chain and it would take three “milkmen” for the red ball (Beaufort) probability to fall below 50% and for a York false paternity event to be probable.

(1) https://en.wikipedia.org/wiki/History_of_snooker

(2) http://www.nature.com/articles/ncomms6631

Post Navigation

%d bloggers like this: