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Archiver > BLEVINS > 2008-12 > 1228179635


From: "Rob Blevins" <>
Subject: [BLEVINS] Blevins Y-DNA Project Update
Date: Mon, 1 Dec 2008 20:04:52 -0500


Cousins,

We've had some exciting developments in the Blevins Y-DNA Project this year. The good news is that we've gained 7 new participants so far this year (results for two are not yet back from the lab) AND we've gained expanded 67-marker results from 8 of our previous participants. The disappointing news is that 4 other men ordered test kits this year but have to date failed to return their samples for testing.

As of this writing our project includes 30 participants with comparable results. Two participants only have 12-marker results, one has 25-marker results, 13 have 37-marker results, and 14 have 67-marker results. One more participant has a 37-marker test being processed by the lab but his results are not yet available.

The analysis of Y-DNA results primarily relies on finding marker MUTATIONS (the small changes that occur throughout the generations). But before we can identify a mutation in a marker, we need to know what the marker looked like originally. That means we need to define a Modal Haplotype for Blevins Y-DNA. Over two years ago, we were able to establish just such a Modal for the first 37 markers. Now, thanks to 14 of our comparable participants who have taken high resolution tests, we have defined a "probable" (albeit not final) Blevins Modal Haplotype all the way out to 67 markers.

Of our 30 comparable participants, at least 18 exhibit one or more mutations. (I say "at least 18" because not all of our participants have 67-marker results available. If their results were extended to 67 markers, it is possible that additional mutations would be revealed.)

Mutations are important because, once they develop, they are passed down to all direct male descendants. We use these mutations to make (or infer) genetic connections between our ancestors because men with identical mutations have a very high probability of being very closely related. But identifying mutations is really only the first step in our process. Because mutations can develop in any generation, it is important to try to "date" about when a mutation first appeared. Our second step, therefore, is to attempt to categorize identified mutations as being either "old" or "recent".

The way we date these mutations is to examine the results of men who share a proven common ancestor. If two proven distant cousins (3rd, 4th, 5th, etc. ) carry the same mutation, we can be reasonably sure that their most recent common ancestor ( 2nd GGF, 3rd GGF, 4th GGF etc.) ALSO carried the mutation. If these same proven distant cousins carry one or more non-matching mutations, we can be reasonably sure that these non-matching mutations developed more recently in their ancestry.

Ideally, we'd like to test every 1st, 2nd, 3rd.. cousin of every participant out to his most distant proven cousin. That way, we could determine the specific generation that spawned a specific mutation. Realistically however, the best we can generally hope for is to determine if a mutation was carried by the oldest proven ancestor or if it developed more recently in the line.

The above really isn't as daunting a task as it sounds because we have quite a few men in our project with proven pedigrees back to a common ancestor.

4 participants share James Blevins (bc. 1770 and married to Lydia Sizemore) as their proven MRCA. One of these men matches our 37-modal but 3 show one mutation each. Because these 3 mutations are all different, we can assume they developed sometime AFTER James (1770). We can further assume that James (1770) himself matched our 37-marker modal. One of these participants has 67-marker results that enable us say that James (1770) probably matched our 67-marker modal as well.

2 participants share Daniel Blevins (bc. 1810 and married to Sarah Corey) as their proven MRCA. Neither man shows any mutation so we can assume the Daniel (1810) matched our 37-marker model. One of these participants has 67-marker results that enable us say that Daniel (1810) probably matched our 67-marker modal as well.

2 participants share William Blevins (bc. 1793 m. Rhoda Pruitt) as their proven MRCA. We are still waiting for final results for one of these men but the results thus far show no mutations for either men on 37 markers. One man does show a mutation at marker #62.

2 participants share Nathan Blevins (bc. 1795 m. Mary Rogers) as their proven MRCA. One shows no mutations out to 37 markers and we are waiting for results on the other.

We probably have 2 participants who share William Blevins (bc. 1786) as MRCA, 2 participants who share Thomas Blevins (bc. 1823) as MRCA, 2 participants who share Levi Blevins (bc. 1779 and married to Mary) as MRCA, and 2 participants who share Elisha Blevins (bc. 1767 m. Rachel Osborne) as MRCA. Some of these relationships are probable instead of proven, some show no mutations at all, and some don't have results beyond 12 markers.

Most of the above analyses have simply allowed us to eliminate mutations as having occurred too recently to be useful to us. The most exciting findings are from what we have come to call the "Tennessee" mutation groups.

2 participants share David Blevins (bc, 1776 m. Sarah Torbett) as their proven MRCA. Both of these men show matching mutations at markers #10 and #58. We can be reasonably sure that David (1776) ALSO carried these two mutations, making him slightly different genetically from the other Blevins ancestors discussed above. (One participant shows an additional mutation that probably occurred more recently.)

2 participants share Josiah Blevins (bc. 1780) as their MRCA. Both of these men show matching mutations at markers #10, #55, and #58 and we can be reasonably sure that Josiah (1780) ALSO carried these three mutations. Like David, these mutations make Josiah slightly different genetically from other Blevins ancestors. Josiah is even slightly different from David because of his extra mutation at #55 AND because David and Josiah have different mutation magnitudes at #58. (Again, one of Josiah's descendant shows an additional mutation that probably occurred more recently.)

Adding to the excitement is one participant who has John D. Blevins (bc. 1811 m. Catherine) as his MRCA and another man from outside of our project who is almost certainly a descendant of Clark B. Blevins (bc. 1817 m. Patience Stout). Both of these men show the exact same 3 mutations exhibited by Josiah Blevins (plus one extra, more recent mutation). We KNOW that neither John D. nor Clark B. Blevins were descendants of Josiah, yet the Y-DNA essentially proves a close relationship.

These six men all share three characteristics in common. They all exhibit a matching mutation at marker #10, a similar mutation at marker #58, and early east Tennessee roots. We have taken to calling their marker #10 value the "Tennessee" mutation. These six men also carry the oldest Blevins mutations we have thus far been able to isolate. The ancestors of these six men also appear to represent two Blevins subgroups, both distinct from other Blevins men within Group A..

The dots are starting to connect and we are finally approaching a critical mass in the project where we can start making meaningful connections. We didn't get to this point simply by chance however. While several of the overlapping pedigree participants have come to the project by random choice, most of them came to the project through vigorous recruitment efforts. Over the past few years, Ron Blevins and I have invested a lot of time, energy, and money recruiting and enticing Blevins men to join the project. Ron is responsible for bringing in all 4 of the James (1770) participants plus several others. I have been the driving force behind the Tennessee participants. We could use some help.

We need more participants.

Although we welcome participation by any Blevins man at any level (12, 25, 37, or 67 markers), we really need 37-marker results or better for meaningful analysis. 67-marker results are even more useful but they are absolutely needed for any participant that exhibits the "Tennessee" mutation. If you are planning to join the project, please order the 37- or 67-marker test. 37-marker tests can always be upgraded to 67-marker results at a later date. If you currently only have 12- or 25-marker results, please consider ordering upgrades.

We still need to "firm up" our 67-marker Modal Haplotype. We have specifically targeted two or three of our current participants for upgrades to 67 markers. They will be contacted directly.

Our database is heavily skewed towards one or two primary Blevins lines. Between 50 and 65% of our participants, for example, are very likely descendants of the James Blevins who was born about 1740 and was married to a woman named Ward. We desperately need more representation from other old lines. I have identified 3 specific lines I consider critical for us: 1) Colonel William Blevins of early Sullivan County TN married to Ann, 2) Dillon Blevins of old Pittsylvania County married to Ann Armstrong, and 3) John Blevins (aka Orator John) of old Grayson County married to Catherine Cox.

I'm sure Ron, Owen, and others can add to this list.

Rob Blevins


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