Group 1 R1b >> BY250>BY3717>BY20217>BY38574>BY38571>Y132125
Blair of Blair

Group 1 is believed to descend from the Blair of Blair. The Blair of Blair goes back to approximately 1200 when Jean Francois, a Norman, was granted Barony of Blare by King William, between 1165 and 1200. The descendants of Jean Francois are believed to the first Blair's. Participant #4816 is a direct descendant of John Blair (b. abt. 1547) and Grisel Sempill. John was Blair of Blair from approximately 1570 to 1609. #4816 is 17 generations removed from John Blair and Grisel Sempill. Participants in this Group are approximately 30 generations removed from the Blair of Blair.

Participant Anc01
Participant Anc01 is the hypothetical "common ancestor" of the participants in Group 1. Although it is impossible to actually know his DNA test results, it is possible to derive his most likely test results based on the results of his descendants (the participants). These results are shown below. Note than these results may change as more participants fall into Group 1 and more test results are available.

25 Marker Matches
All participants in this group have tested at least 25 markers. 30 participants in this group match exactly on all 25 markers and match #4816 on 24 of the 25 markers. 23 others are off by a distance of no more than 1 from this group of 30 and 2 from each other.

The MRCA of #4816 and any Blair in Group 1 would have to be at least 17 generations, back to John Blair and Grisel Sempill.

The table below shows the number of mismatches each participant (who has tested 25 markers) has with any other participant in the group:

37 Marker Matches
56 group 1 participants have tested for the 37 marker test. Seven of the participants match on all 37 markers. The table below shows the number of mismatches each participant who has tested 37 markers has with any other participant in the group. The 56 participants who have tested 37 markers have 42 distinct oldest known ancestors.

Click on the Chart for a larger Image

Five participants (#5891, #9084, #26521, #222156 and 293511) may or may not be descendants of the Blair of Blair. The situation with #9084 and #26521 is complicated by the fact that according to their paper trails they share a common ancestor with #6086. Their relationship can be viewed if you click here.

67 Marker Matches
There are now a total of 18 Group 1 participants who have received their results for markers 38-67. The interesting thing is, that 10 of the 18 participants have the same results on the last 30 markers. The 18 participants who have tested 67 markers have 15 distinct oldest known ancestors.

111 Marker Matches

There are now 15 Blair and Blair related people who have tested to 111 markers.  They are all related at the level of the SNP Y132125, but they diverge below that:  for example #293511 and #240293 are in two different subclades, while #9084 and #B102160 are in the same sublcade. 

The need for upgrading Group 1 Y-DNA

Thanks to Big Y and 111 marker test takers, we are getting a tantalizing glimpse into the structure of the Group 1 Blairs and their relationship to some DNA cousins.  All the members of this larger group tested are positive for the major SNP BY250 (while these designations have a meaning, they really are only names and could just as easily be thought of as being names like Joe, John, George, Ringo, etc). At FTDNA, there are two haplogroup projects for people with the BY250 SNP: R1b Basal Subclades and R1b-BY250-Northern Germanic

Beneath BY250 the next SNP of importance is BY38574, for which time to the most recent ancestor (TMRCA) is currently estimated to have been about 900 years before present (ybp).  At this SNP there is a major branching with the Blair ancestors going one way and some of the Blair DNA cousins going another.  It is as if one father had two sons with one son leading to what today is a group with surnames such as Kerr and Strong, while the other son led to the Blairs.  Remember, this analogy is only as good as the data and, while the branch is real, there might be more DNA cousins branch off at this point.

Further down the Blair tree is the SNP Y13215, currently thought to have a TMRCA of about 650 ybp, where the Blairs seem to branch into two groups.  One branch leads to the SNP BY58038 and the subbranches of Y132100 and Y13290 (genealogy and DNA both suggest a date of 300-350 ybp for this SNP), while the other branch leads to another two arm branching.  One of these latter branches leads to a group of people who all have 67 marker tests, so we don’t know what the SNP status might be, while the other branch leads to another two arm branching.  Of this other branch, one branch leads to a group of people with surname of Stewart, while the other branch leads to Blairs with the SNP BY86278.

Unfortunately, more than half of the available Group 1 sequences are 37 markers or fewer.  The need is great for upgrading these to at least 111 markers or, preferably, the Big Y test.  The reason for upgrading can be seen from the following.  If we simply line up all the sequences available one beneath the other in a table and then look at each column to see if any of the values at that marker are different, we see that 28 of the 111 markers show a difference (and it might be more if there were upgrades).  However, the differences are scattered such that the first 37 markers contain 46 % of the changeable markers, while the markers from 38 to 111 have 54% of the changeable markers.  Thus, while the 37 marker test is valuable for grouping people and verifying near ancestors, it is of no use in trying to determine the greater structure of Blair descent.  Actually the markers between 68 and 111 have 32 % of the changing markers and the 67 markers tests should also be upgraded.  An upgrade can make a material difference, for example, in one case a 67 marker sequence sorted with Blair DNA cousins, but when upgraded to 111 makers the sequence sorted with Blairs.

While we are looking at structure, it might be possible to include genealogy to ask still other questions.  For example, the group of Blairs with the 67 marker test all seem to have an earliest ancestor in the Carolinas, which might possibly mean that they are all related to one person who emigrated early, but will this hold up with upgrades to 111 markers or the Big Y test?  Some of the Blairs from Northern Ireland appear to have landed in the New England area and, while on the surface it appears unlikely, could that possibly mean that only one line of Blairs went from Scotland to Ireland to New England, while others went directly from Scotland to the New World?  Only upgrading the current tests and finding more testers will help answer these and other questions.  

Questions are good.  Keep thinking and asking

To view the graphic version of the above discussion, click here.  The graphic is a representation of our knowlede as of 2 Aug 2020. 

In the graphic:

Blairs are in the color burnt orange.  The off white colors are for Blair cousins.

The boxes with a Big Y label on the upper left can be reasonably assured of their placement.  Those boxes with no Big Y label,  but testing to 111 markers are reasonable in their placement.  Those boxes testing to 67 markers are tentative.

There are no 37 marker tests in the graphic, as they contain too little information to determine where they belong.

The nodes in blue represent one or more ancestors necessary to join the proposed lineages.

IDs in the blue boxes such as BY20217, BY38571, and Y132125 are names of specific SNPs.  All the Blairs in Group 1 should be positive for the SNP Y132125.

This graphic will change as more tests are uopgraded or more people are added. 

Test Results
Clicking on the highlighed Part ID# will bring up the contact information and pedigree chart (if provided) of the participant.