Some people eat, sleep and chew gum, I do genealogy and write...

Thursday, May 25, 2017

On DNA, History and Definitions


Genealogical DNA testing as it is administered today provides reports such as the ones I recently received from both MyHeritage.com and Ancestry.com. I have been commenting on the differences between the two tests and this may ultimately result in my taking an additional test or tests for comparison. But before I get to that point, there are some serious issues that I need to resolve with the way the tests are reported.

My questions and comments are not directed at the procedures or scientific content of the tests, I am merely observing what I would characterize as very "fuzzy" history in the reporting of the results. The results from Ancestry are a very good example of my concerns. My Ancestry.com DNA test produced the following general percentages of genetic matches as follows:
  • Great Britain 55%
  • Scandinavia 29%
  • Other regions 16%
When I expand the analysis, I get the following results:
  • Great Britain 55%
  • Scandinavia 29%
  • Iberian Peninsula 11%
  • Ireland 5%
When I expand the Irish component, I get the following expanded comment.


From my own research, I have ancestors who were born in Northern Ireland and were Protestants and most like came from Scotland. I also have ancestors who were born in Ireland that is now the Republic of Ireland. I also have some ancestors who, through research, clearly came from Wales and others that are definitely English. Now, I get to the issue of the ethnic history of each of these countries; England, Scotland, Wales, Northern Ireland and Ireland.

The British Isles refers to a group of islands in the Atlantic Ocean off the west coast of continental Europe. The earliest name for Great Britain is Albion. The term "Britannia" was used by the Romans after their conquest by Rome which began in 43 A.D. England's claims to Scotland resulted in more than a century and a half of war beginning in about 1174 and ending in 1296. The term "Great Britain" is loosely applied to what is further known as the United Kingdom. Quoting from Wikipedia: Great Britain:
Great Britain refers geographically to the island of Great Britain, politically to England, Scotland and Wales in combination. However, it is sometimes used loosely to refer to the whole of the United Kingdom. 
Similarly, Britain, can refer to either all islands in Great Britain, the largest island, or the political grouping of counties. There is no clear distinction, even in government documents: the UK government yearbooks have used both "Britain" and "United Kingdom".
The full name of the "United Kingdom" is the "United Kingdom of Great Britain and Northern Irland." On May 1, 1707, the United Kingdom of Great Britain was formed as a result of the Acts of Union being passed by the parliaments of England and Scotland to ratify the 1706 Treaty of Union and so unite the two kingdoms.

There is a lot more history, but all this and more illustrates that the terms used by Ancesty.com in communicating the DNA results are even fuzzier than the results themselves. This is especially true when you look at the reference to Ireland which then includes both Wales and Scotland which are clearly, now, part of what is often called "Great Britain."

In addition, none of these quasi-political designations have anything at all to do with genetic ethnicity. The population of Great Britain is extremely diverse. For example, in 1066 A.D. there was a considerable influx of French influence. Telling me that I have a certain percentage of my ancestry from Great Britain and then dividing off Ireland, Scotland and Wales is not only historically naive but really doesn't give me any useful information compared to doing careful genealogical research from historical documents. 

6 comments:

  1. The ethnicity analysis done by the DNA companies is the poorest product they all provide. But it gets the most press and publicity and many people do the test just for it.

    In reality, the useful part are the matches and combination of that with genealogical research to help find new ancestral lines.

    Neither AncestryDNA nor MyHeritageDNA have the tools to do the tools to allow you to do so. You should consider trying or transferring to FamilyTreeDNA or loading your raw data into GEDmatch. Either will give you tools that will allow you to analyze your segment matches and help you investigate your genealogical roadblocks.

    ReplyDelete
    Replies
    1. I agree and I will be writing about that aspect of the tests as I go along. Thanks for the reminder.

      Delete
  2. I believe that the problem is that the sample database against which our DNA is compared is still so small. These ethnic estimates should improve over time.

    ReplyDelete
  3. These ethnicity estimates probably will get better and more specific over time as reference groups tested increase in size.

    ReplyDelete
    Replies
    1. How long will we have to wait and when will we know when the estimates are specific enough?

      Delete