Friday, 2 December 2016

L2 MHT - The Updated "Family Tree" of Lineage II (Dec 2016)

There are currently 31 members in the North Tipperary Gleeson group (Lineage II), 8 new members since August this year and several more on the way. All of them contribute data from at least 37 STR markers to the project. Over the last few months, several people have upgraded their results from 37 STR markers to either 67 or 111 markers.

In addition, we have SNP marker data from 9 Big Y tests, with the results of 1 more test expected shortly (end Jan 2017). This SNP data has identified 4 distinct branches of the North Tipperary Gleeson "Clan" so far, and supplementary analysis of STR data has identified an additional 2 probable branches. This brings the total to 6 distinct branches within the North Tipperary group.

With all this new data, the "Family Tree" for Lineage II can be updated. This tree is also known as a Mutation History Tree (MHT) - in essence it is a Descendancy Tree that combines data on SNP markers and STR markers with traditional genealogical information such as place of birth of MDKAs (Most Distant Known Ancestors) and family nicknames.

A list of all the members of Lineage II is included in a table at the end of this post and includes their "G number", their kit number, and their MDKA (Most Distant Known Ancestor). Find your G number from the table and then see where you sit on the tree.

Below is the updated version of the previous MHT for Lineage II - the North Tipperary Gleeson's. It is in two parts - the first part is the actual tree itself, the second part is the known genealogies associated with each branch. The best way to see the detail of the tree is to click on each image to enlarge it or, better still, download high resolution pdf versions of each part from Dropbox on the links below and refer to it as you read what follows:
The Mutation History Tree for Lineage II (L2 MHT)
(click to enlarge)

The Pedigrees of the North Tipp Gleeson's
(click to enlarge)

So what are we looking at?
The tree starts 4300 years ago, at a branching point in the Tree of Mankind characterised by the SNP marker Z255. The particular individual who carried this mutation became the Great Grand-Daddy of the Gleeson's ... and their various genetic neighbours (including the Treacy's & Miller's, and more recently the McCarthy's, Carroll's, and McMahon's - for further information, refer to Nigel McCarthy's Group E tree here). Further DNA mutations occurred among the descendants of the Z255 individual before one branch became a gaggle of Gleeson's. Where on the tree this actually happened is still not immediately clear, but apparently some time after the BY2852 group of mutations (crudely estimated to have occurred about 200-400 AD) and probably at or after the A5627 group of mutations (crudely, 490 AD), and probably at or before the A5628 mutation (crudely, 1125 AD).

The tree is based on a combination of SNP marker data (in bold brown text) and STR marker data (in black text). How the tree was generated is the subject of a YouTube video here. Back Mutations are highlighted in yellow, and Parallel Mutations are highlighted in green - more about them in a separate blog post. A crude timeline based on SNP data is on the left of the diagram (blue numbers), and the timings for more recent branching points are calculated from STR data - these appear as red numbers below each branching point (or node) and are expressed in terms of the estimated number of generations back to the common ancestor at that particular branching point. These latter estimates use the values closest to the midpoint (50%) estimate from the TiP Reports for the various project members. To convert these to years, I generally assume 30 years per generation and I also assume that the average year of birth of each person tested is about 1950. Thus 5 generations back would be approximately 1800; 11 generations back would be roughly 1600; 14 generations, about 1500; and 22 generations back, about 1300. A key point to remember about all these time estimates is how crude they are - they only give very approximate timepoints, with a very large range around each one.

The main feature of this updated tree is that there are 6 distinct branches (or sub-branches) of the North Tipp Gleeson "Clan". Let's take a look at each branch in turn:

  • Branch A is characterised by a block of 6 SNP markers, starting with the A660 marker. The project members in this group include 3 brothers (G39, G51, G73) whose ancestors emigrated to Ontario, and 2 other members whose ancestors emigrated to the Antipodes (New Zealand & Australia). The common ancestor for these individuals is about 9 generations ago (in crude terms) and so is beyond the reach of paper records.
  • Branch B is characterised by the SNP Y16880 and is shared by 4 people (two of them uncle-nephew). Two families are relatively closely related (with a common ancestor about 5 generations ago or roughly 1800) but both are more distantly related to the third family (the common ancestor being 8 to 11 generations back, i.e. born about 1600-1700).
  • Branch E members have not been SNP-tested yet but are grouped together on the basis of a relatively unique STR marker pattern (signature). Two of them (G91 & G75) are second cousins and are related to the third member about 5 generations back. The two cousins have Gleeson ancestry going back to the townland of Curraghaneddy in the early 1800s. This may be the ancestral homeland for the other member of this sub-branch.
  • Branch C consists of 3 people, two of them related within about 4 generation and the third about 6 generations back. Interestingly, the townland of Garryard occurs as a common location for the respective MDKAs of the first two people (G71 & G22).
  • Branch D is a bit unusual. The two members are very distantly related (about 14 generations back) and each has many mutations not shared by the other. These are likely to be quite ancient branches of the Gleeson "Clan" and I suspect that over time (as more people undertake SNP testing), both of these branches will be subdivided into further sub-branches.
  • Branch F is also a very ancient branch, going back anywhere from 14 to 22 generations ago (crudely, 1300-1500). However, 3 people sit on this particular branch, and two of them (G97 & G98) are related about 5 generations back (about 1800). Our illustrious Chairman (Michael G) sits on this branch and his Big Y results (expected end Jan) will throw further light on the origins of this particular branch.

You can read more about how the tree was put together on the following two blog posts which deal with Grouping of members and Placement of the resultant groups on the tree respectively.

Altogether, the new tree incorporates 20 of the 31 members of Lineage II. What of the remaining 11 members? Well, two of them are Treacy's and belong on the A557 branch (in the top right of the tree). The nine remaining members could not be accurately placed on the tree due to the absence of SNP data and/or distinguishing STR data - we'll take a look at these in a separate post. These members will need to undergo further SNP testing to see where exactly they fit on the tree. But because we already have a lot of SNP data (thanks to the 10 project members who have already undertaken Big Y testing) we will be able to pursue a cost-efficient SNP testing strategy for the remaining members of the project. And that will also be the subject of a subsequent post.

The 31 members of Lineage II
(with "G number", kit number, MDKA, & terminal SNP)
Maurice Gleeson
Dec 2016

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