Motto: Justice and fortitude are invincible

Wednesday, July 2, 2008

Our Family Pursuit...

  • to discover our different McGuire family lines
  • to preserve our family stories and heritage
  • to help each others family research
  • to communicate between family lines

Latest News

Email from Terry Barton -
Sun, 5 Apr 2009
From: Terry Barton

Hi Josiah.


Very Interesting. I appreciate the chance to see such a well tested group of men - with such an extra-ordinary story. I'd love to hear how the learning progresses over time. This could make a good case study for presentation at a future FTDNA sponsored international GG meeting.


I took these results and colorized them so that I could see how the mutations are aligning. Then, I found I had to do some further marking in order to get a clearer view of the pattern. I've attached my spreadsheet - in case anyone is interested.


Going with Leo Little's Null theory, the null at 425 would be a one time event from a relatively distant time - well before the advent of surnames. So, in the broadest sense - and as first step - these men share a "recent" common ancestor - who could have lived a number of 1000s of years ago.


Also, the 3 groups share a number of mutations away from the Atlantic Modal Haplotype - which support an even more recent common ancestor - particularly at:


  • 385b
  • 439 (with the 4 man group showing more mutations)
  • 449
  • 570 (where the larger group added another mutation)
  • 511
  • 425 (the null)
  • 413a
  • 534


So - despite the large number of mutations of separation between the groups - there is a second indication of shared ancestry - more recent the 425 Null. But - then, you have the "challenge" to recent common ancestry:


Mutations for the small group:

  • 393
  • CDYa
  • 444


Mutations for the large group:

  • 19
  • 570
  • CDYb (possibly with a couple of back mutations?)
  • 438 (2 count difference - one or two step mutation?)
  • 406S1
  • 413b
  • 481


So - can 10 mutations (and GD=11) between the apparent common ancestor of the small group and the apparent common ancestor of the large group have occurred since the advent of surnames? Yes - in theory, but it's a low probability. The more likely situation is that there are two more distantly related families (more than 900 or so years) who happened to take the same surname.


44801 would appear to be a singleton from yet another branch who is probably at a large generational distance to the two main groups - many, many 100s of years - and likely well more than 1000 - and closer to the larger group than the smaller one.

Peter - I put your markers into the spreadsheet and see a mixture of some matches to the small group - and some to the large one - which says to me that your connection would predate the advent of surnames - similarly to 44801's situation.


Hope this is of some use. I enjoyed trying to understand how such genetically different men might be related - and when.

Best Regards,
Terry Barton


Also an email from Joseph Donohoe (Administrator of the Breifne Clans DNA Project)
Sat, 14 Mar 2009
From: Joseph Donohoe -


Josiah -

Thanks for your email.


You've certainly looked into this matter with thoroughness. In general, I agree with your line of thinking.


Attached is an excel chart drawn up last Jan with the same focus in mind, the null value at DYS425. The motivation was the group of two Clarks, an O'Reilly, an O'Shea and a Smith who have tested to the 67-marker level in the Breifne Clans Project, plus the two Boylans who have tested only to the 37-marker level. One marker deviating from the Super West Atlantic Modal Haplotype (SWAMH) didn't seem sufficient to identify a group, however, so the two markers bracketing this one (DYS511 & DYS413a), which also deviate from the SWAMH, were included as selection criteria. In searching for haplotypes meeting these criteria it was noticed that quite a few also displayed the same deviations from the SWAMH at DYS385b and at DYS534.


The criteria were tightened to include the deviations at these two markers. The haplotypes meeting these criteria appeared to be mainly associated with the old Oriel surnames of Carroll, McGuire, McKenna and McMahon, as you have independently noticed. Boylan fits into this group, and Clark and Smith are professional surnames which probably arose independently in different parts of Ireland. O'Reilly and O'Shea don't fit, and remain to be explained.


The columns highlighted in yellow show the markers deviating from the SWAMH which extend over several surnames, indicating an origin which either predates the adoption of surnames in the area or which results from a branching off of sub-clans from a senior clan.


There would have to be a comprehensive survey of all the surnames of the area traditionally descended from Cairpri Daim Airgit (d. 513), King of Oriel, in order to conclude what his haplotype might have been. Testing the male-line descendants of three sons is generally considered to be the requirement for determining an ancestral haplotype (two sons if the modal haplotypes match exactly).


The modal of your group of McGuires and that of the other group are very distant, probably more than 2,000 years from a common male-line ancestor, and perhaps eventually will be determined to belong to different haplogroups.




DNA results summary

The majority of participants matching our group are finding that we share a common ancestor back to a unknown McGuire male born around 1700. We don't know when this McGuire family came to America. This McGuire male had at least two sons though, that we are aware of. The two young boy's names were John and Francis McGuire and they were both listed in a 1734 Goochland Co., Virginia court document.

For some DNA participants, their common ancestor would be the father of John and Francis. And for those that are loosely matched with the rest of the group... that common ancestor would be shared much further back; perhaps several hundred years before the father of John and Francis. This is based on the fact that the four "loose matches" have a GD (genetic distance) of 9, 11, 12, and 12 markers that different than the rest of the group... but yet all four share the same null value that the closer participants have. That much GD normally requires many, many years to take place.

Personally, I think it's pretty unbelievable... that through DNA testing we have been able to find a common connection. And that our McGuires are related, and provable through DNA back to the father of these two McGuire brothers almost three hundred years ago! Prior to the DNA testing... most of the participants had no prior knowledge of any of the other families. So DNA testing has been very successful for our group in locating lost families that we had no idea existed.

As previously mentioned, we do have four McGuire participants in our group that Pat Meguire termed as "loose matches". Pat believed, and so has 2 or 3 other administrators, that the "loose matches" must share a common ancestor with the rest of our group going back several hundred years further than the main common ancestor of our group.

Terry Barton, another administrator of another FT-DNA project (and also with ) ran some DNA analysis on our group. You can read his email to me here at this link here DNA testing results , or at the top of this page.

Terry believes our "loose McGuire matches" can be broken down into two additional McGuire groups. These two groups would be the Thomas and Timothy descendants represented in our results. For these two groups a common ancestor with the rest of our McGuires seems to have occurred around 900 to 1000 years ago; or near the time when the “adoption of surnames” was taking place.

So all together, Terry Barton believes our McGuire matches are actually representing three McGuire groups. He believes that all three ancient ancestors choose McGuire to be their surname. So you might say... we were related before we were officially McGuires; and also after we choose to be McGuires! What do you think of the chances of that happening; pretty unbelievable odds... I would guess. Wouldn't that pretty much covers all the bases... (relatedness, both before surnames and after surnames)?

I believe that the DYS425 null could have some interesting implications for some surnames. I believe it may show relatedness to other historical families descended from a common ancient ancestor back in early Ireland. I believe that some of these surnames and ours descend from "Colla da Chrioch", one of the three Collas who ruled in the Kingdom of Orgiall (or Oriel).  See ancient genealogies; author John O'Hart (1824-1902) Irish Pedigrees; Volume I and Volume II.

I do believe that the McGuire surname project can be (more or less) broken down into two groups. There are a few kit numbers in the project that are anomalies; and these are a separate issue. Basically though; there seems to be two groups... those with the 425 null, and those without it. You can read my theories at Ancient traditional history - (McGuire family tree), and it will offer an explanation regarding the origins of these two main groups.

Our McGuire group

Listed below are some unique markers and their values that can help in identifying our group:

  • DYS 425 = null
  • DYS 19 = 15
  • DYS 385b = 15
  • DYS 438 = 10
  • DYS 511 = 9

A null value for any marker indicates that the lab reported a null value or no result for this marker. All cases of this nature are retested multiple times by the lab to confirm their accuracy. Mutations causing null values are infrequent, but are passed on to offspring just like other mutations, so related male lineages such as a father and son would likely share any null values. I think the null value or the RecLOH mutation at DYS 425 shows that our group of 17 are all related to a common ancestor.

The null value mutation is a pretty rare occurrence in genetics; and it seems to run in our McGuire family line. It does however happen frequently in other Haplogroups, especially G, E, and I. For our Haplogroup R1b and it's subgroups it is a more rare occurrence. Once the null value is there in a family, it is passed down from one generation to the next generation. And since we have both "close matches and "loose matches" that have the 425 null value, I believe we all share a common ancestor perhaps over a thousand years ago.

The DYF371X test breaks down the region for DYS 425 into four sub-regions. The DYS 425 region in simpler terms can be thought of as DYS 425a, 425b, 425c, 425d. The DYF371X test looks at the maker values for each of these four regions. The mutation that produces the null value could happen at any of these four regions; either with replacing the allele type, or the marker value. In the case of Mike and I... (and probably everyone else in our group) in the second region a C-type allele has overwritten the T-type allele, and that is causing the test to show a null value at this marker. This happens in what is called a RecLOH event... a mutation event that is passed down from ones ancestors, to all the descendants.


To see all of our McGuire matches in one group; click here: Mag Uidhir Clan - DNA (scroll midway down) Look for group labeled " Mag Uidhir Clan I " - our null values are displayed as ( 0** ) in the column for the DYS 425 marker. The DYS 425 null can only be tested at the 67 marker level. I would urge that the rest of our group upgrade their kits to 67 markers... if they haven't already.

For more information on null values, and DNA markers, please see these links:

RecLOH at Wikipedia
Diagnostic Y-STR Markers in Haplogroup G by Phillip G. Goff and T. Whit Athey

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