Updated DNA Ethnicity Estimates

Earlier this year I posted a short piece that compared my DNA ethnicity estimates provided by a few different companies to each other. Ethnicity estimates are great cocktail party conversations, but not terribly useful to people doing serious genealogy research. They are highly dependent upon the available data from reference populations.

To put it another way, if nobody in a certain ethnic group has tested with a company, there’s no real way for that company to place your results within that group. In the United States, Native Americans are known for their reluctance to participate and, last I heard, they are under-represented in ethnicity estimates. Fortunately for me, Western European population groups are fairly well tested.

But these reference populations are constantly being updated and new analysis being performed to try and sort people into ever more distinct genetic communities. (Although generally speaking the utility of these tests only goes back a handful of generations.)

Last night, when working on a different post, I received an email saying Ancestry.com had updated their analysis of my DNA. So naturally I wanted to compare this most recent update to last September’s.

Still mostly Irish

Sometimes when you look at data and create data visualisation pieces, the story is that there is very little change. And that’s my story. The actual number for my Irish estimate remained the same: 63%. I saw a slight change to my Scottish and Slavic numbers, but nothing drastic. My trace results changed, switching from 2% from the Balkans to 2% from Sweden and Denmark. But you need to take trace results with a pretty big grain of salt, unless they are of a different continent. Broadly speaking, we can be fairly certain about results at a continental level, but differences between, say, French and Germans are much harder to distinguish.

The Scottish part still fascinates me, because as far back as I’ve gone, I have not found an identifiable Scottish ancestor. A great-great-grandfather lived for several years in Edinburgh, but he was the son of two Ireland-born Irish parents. I also know that this Scottish part of me must come from my paternal lines as my mother has almost no Scottish DNA and she would need to have some if I were to have had inherited it from her.

Now for about half of my paternal Irish ancestors, I know at least the counties from which they came. My initial thought, and still best guess, is that the Scottish is actually Scotch–Irish from what is today Northern Ireland. But I am unaware of any ancestor, except perhaps one, who came from or has origins in Northern Ireland.

The other thing that fascinated me is that despite the additional data and analysis the ranges, or degree of uncertainty in another way of looking at it, increased in most of the ethnicities. You can see the light purple rectangles are actually almost all larger this year compared to last. I can only wonder if this time next year I’ll see any narrowing of those ranges.

Credit for the piece is mine.

Difficult Descendancy Charts

The holiday break is over as your author has burned up all his remaining time for 2020 and so now we’re back to work. And that means attempting to return to a more frequent and regular posting schedule for Coffeespoons.

I wanted to start with the death of Diego Maradona, a legendary Argentinian footballer. He died in December of a heart attack and left behind a complicated inheritance situation. To help explain the situation, the BBC created what in genealogy we call a descendancy chart. You typically use a descendancy chart to show the children, and sometimes grandchildren, of a person. (You can also attach people above the person of interest and show the person’s ancestral families.)

This is an example of a descendancy chart from my research into an unrelated family.

The descendants of Samuel Miller

You can see Samuel Miller married Sabra Clark and had at least nine children with her. And I followed one of them, another Samuel, who married Elizabeth Woodruff and they had four children. In this version, you can also see Samuel the elder’s parents and siblings.

But Diego presents a complicated situation. He was married and had two children, then divorced. That’s not terribly uncommon. But he then went on to have potentially eight children with potentially five different women. (I say potentially because some of the claims are still working their way through the courts via paternity tests.)

The above type of chart works well with one couple. In my own family, I have at least one ancestor who had potentially two husbands (the second marriage has not yet been confirmed, but she definitely had children with two different men). And when we use this chart type to look at my ancestor’s descendants, you can see it becomes tricky.

Mary Remington’s descendants

Her children’s fathers can be placed to either side and then the children flow out from that. But whereas in the first chart we could see all nine children in one glance, Mary Remington had four and we only see two in this same view.

So how do you deal with one person who has six total relationships that have offspring?

The BBC opted for a vertical chart that uses colour to link the couples. Diego and his ex-wife receive a red line, and that link moves vertically down from Diego with the two daughters shown as descendants on the right.

Diego Maradona’s descendants

Each subsequent relationship with offspring receives its own colour and continues to move vertically down the page, linking the mother on the left to the children on the right.

What I find interesting is the inconsistency within the chart, however. At the end, with the unidentified women, we have two instances of multiple children. Santiago Lara and Magali Gil, for example, descend from one stem. But note at the top how Diego’s two daughters Gianinna and Dalma each receive their own stem. Is there a reason for combining the two children from one unidentified mother into one branch?

And why the vertical format? You can see in my two examples, we are looking at a horizontal format. It works well when I am working on my desktop. The format is less useful on a mobile. I wonder if the BBC knows from their analytics that most people access their content like this via mobile phone and created a graphic that best uses that tall but narrow proportion. Because the proportions do not work well when the article is viewed on a desktop.

The vertical descendancy chart here is an intriguing solution to show descendants from multiple partners in a single mobile screen display. I am not sure how useful it would be as a new form, because I am not certain of how many times we would run into issues of children from six partners, but it could be worth exploring.

Credit for the images from my examples goes to the designers at Ancestry.com.

Credit for the BBC graphic goes to the graphics department of the BBC.