DNA, Genealogy, and Geo-political Entities

Europe in 1910

If you have been one of the millions of people who have taken a genealogically motivated DNA test in the last few years, you probably received results that included a list of ethnic origins based on the results that included a map showing the present political boundaries of countries with a generally defined area of "ethnic match." The common definition of "ethnicity" is "the fact or state of belonging to a social group that has a common national or cultural tradition." See Dictionary.com. The descriptions of these "ethnic" groups from the genealogy companies include labels such as the following:

• English
• Irish
• Italian
• England, Wales, and Northwestern Europe

What is the correspondence between current political boundaries and ethnic groups? If a DNA test results say that my "ethnicity is "English" what does that mean? Is there a single social group in the present day country of England that has a common national or cultural heritage? Has there ever been a single social group in England that had a common national or cultural heritage? Can you lump England, Wales, and Northwestern Europe into a single ethnic group?

What are the DNA tests results actually saying when they give you an ethnicity estimate? Political boundaries in Europe have been in a state of constant change for as long as there have been separate political entities. The boundaries of ethnic groups, if they actually exist, do not correspond to political boundaries.

Let's take England or English as an example. What is the English ethnic group? In 2105 results of an Oxford University study showed the following quoted from an article entitled "Who do you think you really are? A genetic map of the British Isles":

• There was no single 'Celtic' genetic group. In fact the Celtic parts of the UK (Scotland, Northern Ireland, Wales and Cornwall) are among the most different from each other genetically. For example, the Cornish are much more similar genetically to other English groups than they are to the Welsh or the Scots. 
• There are separate genetic groups in Cornwall and Devon, with a division almost exactly along the modern county boundary.
• The majority of eastern, central and southern England is made up of a single, relatively homogeneous, genetic group with a significant DNA contribution from Anglo-Saxon migrations (10-40% of total ancestry). This settles a historical controversy in showing that the Anglo-Saxons intermarried with, rather than replaced, the existing populations.
• The population in Orkney emerged as the most genetically distinct, with 25% of DNA coming from Norwegian ancestors. This shows clearly that the Norse Viking invasion (9th century) did not simply replace the indigenous Orkney population.
• The Welsh appear more similar to the earliest settlers of Britain after the last ice age than do other people in the UK.
• There is no obvious genetic signature of the Danish Vikings, who controlled large parts of England ('The Danelaw') from the 9th century.
• There is genetic evidence of the effect of the Landsker line – the boundary between English-speaking people in south-west Pembrokeshire (sometimes known as 'Little England beyond Wales') and the Welsh speakers in the rest of Wales, which persisted for almost a millennium.
• The analyses suggest there was a substantial migration across the channel after the original post-ice-age settlers, but before Roman times. DNA from these migrants spread across England, Scotland, and Northern Ireland, but had little impact in Wales.
• Many of the genetic clusters show similar locations to the tribal groupings and kingdoms around end of the 6th century, after the settlement of the Anglo-Saxons, suggesting these tribes and kingdoms may have maintained a regional identity for many centuries.

So, if your DNA test says your ethnicity is English, which English is that? Even if the "ethnicity" area shown on your map is a blob rather than a defined area, how many different ethnicities are contained within that blob? What is certain is that the present political configurations of countries around the world do not reflect any ethnic boundaries.

Here is another example of the problem. Some of my ancestors have lived in America for about 400 years (399 years to be exact). My genealogical research clearly shows that most of them came from England, Scotland, Wales and Ireland. However, they have intermarried over those 400 years with people from other locations. Looking at my researched family lines at the great-great-grandparent level here is the makeup of my lines by birth country:

• United States
• United States
• England
• England
• Denmark
• Denmark
• England
• United States
• United States
• United States
• Ireland
• United States
• Denmark
• Denmark
• Wales
• England

What happens if we go back another generation? Fortunately, I have the birthplaces of all 32 of my ancestors at the Great-great-grandparent level and as would be expected, the birthplaces are exactly consistent with the makeup of the countries at the next more recent generation. Why don't any of the estimates show America as an ethnicity? How long do I have to live here before my 400 years of ancestors come from America?

These question actually tell us a lot about genealogy ethnicity estimates. They are in fact estimates and they are based on the ethnicity definitions determined by the testing companies. Interestingly, the companies could have given me the same estimate without the DNA test, based on the content of my family trees and as a matter of fact, the paper estimate from examining my online family tree would be more accurate than the DNA tests.

How do you define what it means to be English? Or Welsh? or German?

So why do I need a DNA test to tell me my ancestors came from England? Why don't any of my ethnicity estimates show my ancestors in the United States for almost 400 years?