Genetic Genealogy - DNA to the rescue??

I'm an old-fashioned genealogist at heart. Well, sort of. I grew up as the online genealogical community evolved, was an early adopter of Rootsweb back when it was mostly mailing lists, and a frequent user of Findmypast when it was still 1837online. Don't get me wrong, I love the thrill of proper, tangible archival research as much as the next archaeologist-turned-family-historian, but online genealogy has always been my first go-to point. Despite all this, I have been slow to embrace the "big new thing" in family history research - the vast new potential of DNA research.

I can probably blame my reluctance on a nebulous and ultimately groundless scepticism about how my DNA information might be used, most likely born of watching too many crime dramas and reading too many conspiracy theories. Fundamentally, however, I am a researcher and, after scrutinising the small print, I was able to reassure myself that the big players in genetic genealogy do actually value the ethical use and security of their users’ DNA. Indeed if they didn’t it would be very bad for business! So, a few weeks ago I took the plunge, spat in a little tube and sent off my sample to the laboratories of AncestryDNA.*

My AncestryDNA Ethnicity graphic. Clicking on this revealed more detailed information about the UK regions my most recent ancestors were from.

​A fortnight or so later and the secrets of my DNA were ready to be revealed. Well, again, sort of. AncestryDNA provide their results in two sections – a breakdown of ethnicity and a list of DNA matches whose own tests show that they share some part(s) of your DNA. For me, the former part, the ethnicity, was frankly a bit boring. It revealed the entirely expected combination of Northern England and Scottish/Irish, with a tiny bit of Norwegian that can probably be put down to an errant Viking somewhere way back when. Far more interesting from my point of view, however, were the matches. 

My family tree, as so many others, features several illegitimate children. In each of these cases, birth certificates and baptismal records listed no father’s name; no-one had ever sued for bastardy payments or their more modern counterpart, child support. Consequently, parts of my family tree have been built on the testimony of family members, rather than arguably more accurate (or at least less biased?!) documentary evidence. Other parts were completely missing, most significantly my maternal grandfather’s paternal line. He and his older sister were born illegitimately in the early part of the twentieth century; they had never been told the identity of their father and no records or family gossip had ever revealed it.  I had no way to fill in those gaps or to verify whether my other guesswork was accurate. No way, that is, until I received my DNA results.

My grandad, George, and his older sister, Jenny, pictured c.1923, Prestonpans, Midlothian

AncestryDNA lists its matches according to how close a relationship their results suggest. My list contained no close relations (parents, siblings, cousins, 2nd cousins), a single 3rd cousin and 254 “4th-6th cousins”. Despite their distance, however, these matches proved fascinating. For a start, the 3rd cousin and several of the 4th-6th cousins linked to my own paternal line, securing once and for all that the family gossip in that regard was accurate. But what about my grandfather's paternal line? Could my DNA hold the key to solving this 100 year old mystery once and for all?

Yet again, sort of.  As you can probably imagine, I have a very extensive tree on Ancestry, thousands of ancestors taking all my (researchable) lines back at least 7 generations. I was able to compare this with public trees made available by some of my DNA matches, partly by hand and partly using Ancestry's ThruLines (Beta) system which aims to identify common ancestors. Consequently, I could work out how I was related to many of my 4th-6th cousins. Yet it also became apparent that there was a significant group of matches that had no relation to my family tree whatsoever. Looking through their trees, it was clear that many of them had relatives from the small group of villages in rural Midlothian where my grandad and his sister had been born, yet none related to his mother's branch at all. There was only one obvious conclusion - these must be the genetic relations of my grandad's biological father.

Working out exactly who this man might have been, however, was a much more complicated (and ongoing) process. I began by scrutinising the closest match within this group who I'll call TA67 (the number denotes how many centiMorgans we apparently share - more on those later!). She had a few Midlothian branches, so I needed to narrow down which was the correct one. Using Ancestry's Shared Matches feature, I made a list of all the people who had matched both me and TA67. Then I followed that with the Shared Matches I had with those people, and so on. What resulted was a complicated venn diagram of matches, all somehow related to me through this missing Scottish line.

The venn diagram of matches with TA67 in the centre. Bold matches had built family trees that I could compare to narrow down our common ancestors.

Now, before I go any further, I should mention that matching relatives using DNA is not an exact science. DNA inheritance is actually a bit of a lottery. Siblings each get parts of their parents’ DNA, but not the same parts; so cousins will all have parts of their grandparents’ DNA, but again, not necessarily the same parts, and so on. So as you get further from the shared ancestors, the less DNA you are likely to share and the more likely it is that genuinely related people might not show up as a match on a test like this at all. In genetic genealogy, the amount of shared DNA is measured in centiMorgans (cM) – the higher the number, the closer the match. TA67 was my closest match, but 67 shared centiMorgans suggested she was probably no closer than a 4th cousin. Many of the other matches in my venn diagram shared far fewer cMs; I stopped listing them at 20 although there were many more, all the way down to just 7cM shared. All this means that all the people in my venn diagram shared ancestors with me. BUT, just because some of them didn't match with eachother (or because others matched with them and not me) didn't necessarily mean that they too didn't share ancestors; the DNA lottery might just have doled us out completely different hands.

Anyway, by comparing those matches who had connected public family trees, and those who kindly allowed me to view their private trees, I could narrow it down. Yes, you've guessed it - sort of. You see, one cross section of these matches shared one set of ancestors with TA67 and another set shared a different set of ancestors with her, because several generations back in TA67's tree, a set of three siblings had married another set of three siblings, and a couple of cousins married another couple of cousins on the same pair of lines; this made at least five lines of double cousins. Since I matched people on both sides of this tangled web, it was likely that my grandad, like TA67, also shared both these sets of ancestors. The waters are muddied further, however, because double cousins are genetically more related than ordinary cousins so sometimes relations show up with more centiMorgans than they might otherwise have. 

At this point, my head was beginning to swim. I had it narrowed down to 11 cousins, descended from both of the common ancestors, alive and old enough to have fathered a child in 1919. My DNA journey had probably taken me as far as it could. Well, I have convinced my mum to send off a sample of her own in the hope that the DNA of my grandad's daughter might provide some sharper matches and I've reached out to some descendants of these 11 cousins in case any good old family gossip might have been passed down on their side but I accept that I may never get any further. Nevertheless, DNA had already provided what I think is a major clue to the circumstances surrounding my grandad's birth. 

My grandad's mother, Jessie, pictured in the early 1920s, Bonnyrigg, Midlothian.

The stigma of having illegitimate children in rural Scotland in 1918 and 1920 was brutal. My grandad's mother, Jessie, came from a staunchly traditional, Scottish Presbyterian family, exactly as you might expect from a distant relative of John Knox the Great Reformer. Although she was fortunate that they allowed her to keep her children and raise them for a time, she was derided by her relatives and, when she eventually married in 1926, she was forced to leave her daughter and son behind to live with her parents. Jessie refused ever to reveal the identity of my grandad's father to him but insisted that he and his sister had the same one. If true, this would suggest a long-term relationship between at least 1917 and 1920. So why couldn't this relationship end in marriage?

This time, DNA may well have the answer, because whichever of those 11 cousins my grandad's biological father turns out to be, one thing is certain: he was not a Scottish Presbyterian but a Roman Catholic Irish immigrant. During this period in Scotland's past, prejudice against Irish Catholics was strong. In 1923, the Church of Scotland issued one of the most controversial reports in its history. Entitled The Menace of the Irish Race to our Scottish Nationality, it attacked Irish Catholics as drunken, fraudulent criminals and called on members of the church to guard the "racial purity" of virtuous Presbyterian Scotland. Although ultimately rejected by the church in the wake of the toxic European eugenics of the 1930s and 1940s, it sends a clear message about the tensions between Irish Catholics and Scottish Presbyterians during the period surrounding my grandad's birth. A marriage between a Scottish Presbyterian woman and Irish Catholic man would have been unthinkable.

Of course, I will never know the real details of the story and appreciate there are many possible scenarios that might explain how Jessie ended up with two illegitimate children in the early 1920s. Yet this new information paints a picture I would never otherwise have considered, portraying Jessie not as "awf'y common" as her daughter-in-law once described her, but as a tragic heroine, in love with a man whom she would never be allowed to marry.

So, for me, my dalliance with AncestryDNA has been incredibly revealing, answering (or almost answering) questions that documentary evidence and collective family memory simply never could. Yet it was not an easy road. Without a considerable amount of detective work, cross-matching my own extensively worked-out tree and those of my matches, I would never have been able to work out how our family histories intersected. It was that foundation of traditional family history research that made the DNA matches meaningful. DNA research is not a magic bullet. It cannot provide an “insta-tree” (unless you are lucky enough to link to a sibling or 1st cousin who has done the research for you!). But, if you have an established family tree that you would like to verify or if your tree, like mine, contains questions of illegitimacy, adoption or estrangement that simply cannot be addressed by conventional research, then DNA could indeed provide that vital missing link.**

* All this is based on an AncestryDNA test bought for £59 +p&p on in April 2019 (during their Mothers’ Day sale; usual price £79 +p&p). I have yet to explore DNA tests from other companies but will keep you updated if I do in the future!

** If you need a quick, accurate family tree to make the most of your DNA results, try our Essentials Package; or, if you need help making sense of the matches you have, contact us to see if we can help.