Sunday 13 November 2016

The Chairman joins Lineage II

There's been a recent development with Lineage II. A very distant relative has just joined the group.

Michael G. Gleeson
Chairman of the Clan Gathering
Michael Gleeson (MGG-1202), Chairman of the recent Gleeson Clan Gathering, has been sitting in the Ungrouped section since he joined the project some 6 months ago. On his Y-DNA-37 test, his Genetic Distance to members of Lineage II was 8/37 or greater, suggesting no close relationship.

However, on reviewing Michael's results, it became apparent that the terminal SNP markers of his closest matches were usually below Z255, the upstream SNP marker shared by everyone in Lineage II. This got me thinking ... could Michael possibly be a distant match to everyone else in Lineage II?

We set out to explore if this hypothesis could be correct.

First off we tested him for the single SNP marker Z255, just to confirm that he was indeed positive for this upstream SNP. And he was. 

Then we did the Z255 SNP Pack which contains 108 SNP markers below Z255 (i.e. further downstream on the Human Evolutionary Tree, the Tree of Mankind). And (surprise, surprise) he tested positive for the downstream SNP markers Z16437 and BY2852. This is illustrated by the green text in the diagram below (green text means he tested positive for these particular SNP markers, red means he tested negative, muddy yellow means he is "presumed positive" for those SNPs, and blue are downstream SNPs that he has not as yet been tested for).

Michael's current position on the Tree of Mankind
(he's making good progress)

The SNP marker BY2852 (red arrow below) is also shared by all the Gleeson's in Lineage II, but not exclusively so. There are two Carroll's who share this SNP marker. So theoretically, whilst it looks most likely that Michael does indeed belong in Gleeson Lineage II, there is an outside chance that he could be a Gleeson by name and a Carroll by DNA. For example, some time back in the 1500's, a Carroll baby might have been adopted by a Gleeson neighbour. The baby was Carroll by DNA but became Gleeson by name. And so too all his descendants ... Carroll by DNA, Gleeson by name. 

However, this seems unlikely because Michael is more genetically distant from the Carroll's (minimum GD = 11/37; calculated from the Z255 Project Results Page) than he is from other Gleeson's in Lineage II (min GD = 8/37). And in addition, an alternative explanation could be that the two Carroll's are Carroll by name but Gleeson by DNA. It is difficult to know which came first - the Carroll chicken or the Gleeson egg.

The Gleeson portion of the Tree of Mankind
(from http://ytree.net/DisplayTree.php?blockID=16)

Furthermore, shortly after Michael's results came in, a new member joined the project (PG-4241), and this member was a close match to Michael (Genetic Distance of 4/37). They appeared in each other's matches list. And shortly after that, another close-ish match (5/37) joined the group (WG-7908; someone who tested at the Clan Gathering in August). So it looks like the three of them have formed their own particular sub-branch of the Gleeson Family Tree, with a common ancestor born sometime around 1600-1700 or so.

Confirmation that they belong in Lineage II could be achieved by further testing with the Big Y test. This would identify which further downstream SNP markers they test positive for. And it would also help give us an estimate for when this particular sub-branch broke away from the rest of Lineage II (it may have been shortly before 1600).

In any case ... welcome to Lineage II, Mr. Chairman.
Maurice Gleeson
Nov 2016

Update (19th Nov 2016)
I am very happy to announce that Michael has just ordered the Big Y test in the FTDNA Christmas Sale. The price is reduced to $525 from $575 but we used an additional $100 off coupon to get it for $425 - the cheapest it has ever been.

The results should be back some time after Christmas and I suspect they will create a whole new branch on the Tree of Mankind above. And if we are very lucky, they may even split up the SNP Block at the A5629 level (which currently consists of 4 SNPs). The results will also help us get more accurate date estimates for the various branching points in this portion of the Tree. And they will also help in putting together the SNP Panel for Gleeson Lineage II which will make it easier and cheaper for project members to do downstream SNP-testing. I am currently putting this panel together with Thomas Krahn from YSEQ.









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