As funding and opportunity present themselves, we are continuing to upgrade our Kennedy family volunteers' DNA tests in an effort to pin down the origins of our common ancestor, David Kennedy of Russell County, VA (b ? - d 1800).
Late last year, we ran an R1b-M343 Backbone test to begin narrowing down our line's haplogroup to see if our ancient origins might shed any light on our more recent ones.
The backbone test identifies a tester's haplogroup by analyzing the SNPs ("snips"), Single Nucleotide Polymorphisms in our DNA. SNPs are the unique mutations on the Y-chromosome that have happened over thousands of years. They are passed down from father to son, so the larger the percentage of the population who shares a mutation, the longer ago it happened. Conversely, the smaller the percentage of the population who who shares a mutation, the more recently it happened (and therefore the less time it's had to be passed down). By looking to see whether a group of testers has a specific mutation known to be older or newer, it is possible to group them more accurately within a historical or genealogical timeframe.
If you think of humanity as an inverted tree, it began to fork from a common trunk very far back in time. From those early forks came distinctly shaped smaller limbs, and from those limbs came still smaller unique branches and finally the twigs which are nearest the top of our human tree (or the bottom, in genealogical charting terms). Most western Europeans come from the very early R-M207 fork of the tree close to the trunk. R-M207 is estimated to have arisen during the Upper Paleolithic era sometime between 19,000-34,000 years ago. As time went by, mutations caused new branches to begin growing off of the main R-M207 fork, all the way up (or down) to the little twigs that have come into existence only a few thousand or even hundred years ago.
Our backbone test yielded a haplogroup designation for our Kennedy family of DF21. There is disagreement about precisely when the DF21 Haplogroup branched off the tree, although a recent archaeological discovery and subsequent testing indicates it probably originated close to 4,600-4,700 years ago.
At the present, there isn't a lot of information to share about our ancient DF21 ancestor. The overview on the DF21 and Subclades Project on Family Tree DNA is heavy on genetic minutiae like individual marker values and specific mutations, and light on implications and conclusions about our origins or ethnicity. There are several websites dedicated to subclades (the smaller limbs and twigs that have grown from DF21), but I don't believe any would apply specifically to our line of Kennedys, since they focus on parallel branches and individual family groups.
One development of some interest is the aforementioned news in December from Dublin that a team of geneticists and archaeologists had recently completed sequencing the genomes of four ancient inhabitants of Ireland. One of those samples came from a skeleton called Rathlin Man 1 who shared our DF21 ancestor.
Rathlin Man 1 was discovered in a Bronze Age cist on Rathlin Island off the coast of County Antrim in present-day Northern Ireland. Rathlin Island is the northernmost point in Ireland and only 11 miles from Scotland's Mull of Kintyre. This man's bones were carbon-dated to 2025-1885 BC, and he carried a few unique mutations which would have taken 600-700 years to develop, so his discovery allows us to make an educated guess that our common DF21 ancestor likely lived 4,600-4,700 years ago.
While this is interesting, without significant additional contextual history for this man and his surrounding Bronze Age neighbors, it is hard for us to draw any useful cultural conclusions other than confirmation that our DF21 relatives can be found in northeastern Ireland as early as 2025 BC (which isn't to say they were confined to that area, or even confined to Ireland). An article in The Guardian provides fascinating details about what was learned from the genomic sequencing performed on the Rathlin men and a 5,000 year old farmer woman found near Belfast.
Although we have not yet attempted to narrow down our Kennedy lines's haplogroup any further, I strongly suspect that should we do so, we would get a downstream result of L1337. We share unique mutations in our STR (Short Tandem Repeat) values with other Y-67 testers who have been identified as L1336 and L1337. These two designations are smaller "family branches" off of the limb S5488, which grows straight off of DF21. The website PetersPioneers.com does a nice job of providing understandable information and diagrams about all of this if you'd like to learn more.
Based on our assumption that our Kennedys will be L1337's, I had a look at the current public results chart for the DF21 Haplogroup project to see where other L1336 and L1337 testers come from. If you look at the chart you will see the L1336/1337 testers about halfway down in Groups J1a, J1b J1c and J1d. I predict we will fall within J1c, but can't confirm that without testing. Bear in mind that we don't know when we shared a common ancestor with the other testers represented in Groups J1a-J1d, but it was probably much more recently than 4,700 years ago. Realistically, it may have been as recently as a few hundred to a thousand years ago. I wish I could be more precise, and as more testing is done, we may become so, but for now, it's an unknown.
Many testers do not provide information regarding their most distant known ancestor, but some do. Using what was available, I began mapping the known points of origin of genetically similar L1336 and L1337 testers on a Google Map. A number of the men who provided data can only trace their ancestors into Ireland as far back as the 18th or 19th centuries, so while the places they identify are typically reliable, there is plenty of opportunity for their ancestors to have spread out across Ireland from any ancient single point of origin over the intervening millennia. Ireland is small, and ancient people were surprisingly mobile.
My hope, is that as time goes by and we acquire more close genetic matches from our STR and SNP testing efforts, we will see a distinct cluster of matches emerging on the map. That may give us some sense of where we should be looking for our David Kennedy's roots in Ireland. One thing that I can say with a degree of certainty is that many of the names that share distinctive SNP values with our Kennedys are considered Irish in origin. I think it's safe to say that our Kennedys are likely of recent Irish origin (vs Scots, English or Scandinavian). And speaking as a genealogist, "recent" is a relative term (Ha-haha! I crack myself up -- a "relative" term? "Genealogy?")
Although we do have L1336/37's as far away as Wales on our map, the highest frequency of matches so far comes from County Clare, between Galway Bay and Limerick. This sample, however, is far too small to allow us to draw any conclusions. While this area is the historical seat of the O'Kennedy family, if we had been part of that family group, I would have expected at least a few Y-DNA matches with others of the Kennedy surname (of which we currently have none).
So that's the current state of things.
To summarize, SNP testing has confirmed that we fall into the DF21 Haplogroup, which probably originated 4,600-4,700 years ago and has recently been proven to have been in northeastern Ireland by at least 1885BC. Further testing would likely result in a designation of L1337 for our Kennedys, and based on a very small sample of known origins of other L1336 & L1337 testers, there appear to be several whose recent origins are in County Clare between Galway and Limerick.
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