Comparing results from actual recorded ancestry, to that predicted by Ancestry.com, 23andme, My Heritage, Living DNA, FT-DNA and more.
Recorded Ancestry
Results
Comparing results from actual recorded ancestry, to that predicted by Ancestry.com, 23andme, My Heritage, Living DNA, FT-DNA and more.
If there is anyone out there reading this blog, you know my recorded ancestry - all SE English, mainly East Anglian. No recorded evidence of anything but English over the past two or three centuries. This is not to say that I don't think any actually happened.
I have taken several DNA tests for ancestry, including those provided by the FT-DNA, 23andMe, and Living DNA companies. Unusual for a tester, I am actually of a single population, very local, well documented ancestry here in East Anglia, South-East England. I'm not someone in the Americas or Australia, that might have very little clue what parts of the world that their ancestors lived in, previous to immigration. I know my roots, I'm lucky. I live them. You might ask, why did I feel the need to test DNA for ancestry? The answer is, curiosity, to test the documented evidence, fill the gaps, look for surprises, and in particular, to understand the longer term, to reach further back into my ancestry.
I have though, become a bit of a skeptic, even a critic, of autosomal DNA (auDNA) tests for ancestry. They are the tests presented by the businesses in results called something like Ancestry, Family Ancestry, Origins, Family, Composition, etc. Instead of testing the haplogroups on either the direct paternal (Y-DNA), or direct maternal (mtDNA), these tests scan the autosomal and X chromosomes. That's good, because that is where all of the real business is, what makes you an individual. However, it is subject to a phenomena that we call genetic recombination (the X chromosome is a little more complicated). This means that every generation circa 50% of both parents DNA is randomly inherited from each parent. I said randomly. Each generation, that randomness chops up the inherited segments smaller, and moves them around. After about seven or eight generations, the chances of inheriting any DNA from any particular ancestral line quickly diminishes. It becomes washed out by genetic recombination.
Therefore, not only are the autosomes subject to a randomness, and genetic recombination - they are only useful for assessing family admixture only over the past three hundred years or so. There is arguably, DNA that has been shared between populations much further back, that we call background population admixture. It survived, because it entered many lines, for many families, following for example, a major ancient migration event. If this phenomena is accepted - it can only cause more problems and confusion, because it can fool results into suggesting more recent family admixture - e.g. that a great grandparent in an American family must have been Scandinavian, when in fact many Scandinavians may have settled another part of Europe, and admixed with that ancestral population, more than one thousand years ago.
DNA businesses compare segments of auDNA, against those in a number of modern day reference populations or data sets from around the world. They look for what segments are similar to these World populations, and then try to project, what percentages of your DNA is shared or similar to these other populations. Therefore:
It is far truer to say that your auDNA test results reflect shared DNA with modern population data sets, rather than to claim descent from them. For example, 10% Finnish simply means that you appear to share similar DNA with a number of people that were hopefully sampled in Finland (and hopefully not just claim Finnish ancestry) - not that 10% of your ancestors came from Finland. That is, for the above reasons, presumptuous. It might indeed suggest some Finnish ancestry, but this is where many people go wrong, it does not prove ancestry from anywhere.
This is my main quibble. So many testers take their autosomal (for Family/Ancestry) DNA test results to be infallible truths. They are NOT. White papers do not make a test and analysis system perfect and proven as accurate. Regarding something as Science does not make it unquestionable - quite the opposite. The fact of the matter is, if you test with different companies, different siblings, add phasing, you receive different ancestry results. Therefore which result is true and unquestionable?
So what use is DNA testing for ancestry? Actually, I would say, lots of use. If you take the results with a pinch of salt, test with different companies, then it can help point you in a direction. Never however take autosomal results as infallible. Critical is to test with companies with well thought out, high quality reference data sets. Also to test with companies that intend to progress and improve their analysis and your results.
For DNA relative matching, then sure, the companies with the best matching system, the largest match (contactable customer) databases, and with custom in the regions of the world that you hope to match with. There is also, GEDmatch. Personally, I find it thrilling when I match through DNA, but in truth, I had more genealogical success back in the days when genealogists posted their surname interests in printed magazines and directories.
The results of each ancestry test should be taken as a clue. Look at the results of testers with more proven documented and known genealogies. Learn to recognise what might be population background, as opposed to recent admixture in a family. Investigate haplogroup DNA - it has a relative truth, although over a much longer time, and wider area. Just be aware that your haplogroup/s represent only one or two lines of descent - your ancestry over the past few thousand years may not be well represented by a haplogroup. Investigate everything. Enjoy the journey. Explore World History.
Family Tree DNA (FTDNA) have released a new, unexpected feature to their autosomal DNA Family Finder package. It is clearly aimed at their customers (both new and existing), of mainly European heritage. It uses ancient DNA references to plot our ancient ancestry. It breaks European's ancient Eurasian ancestry down into four groups:
First of all, I welcome this new analysis. Combined with the latest cutting edge research into the origin of the Eurasians, and with other open source calculators of ancient origin available via GedMatch - I feel that it can help us get personal with our ancient Eurasian roots.
However... unfortunately it has faults, as the online community quickly picked up. In particular, with the Metal Age Invader component. FT-DNA suggests that it represents the Yamnaya admixture event - where Copper or Early Bronze Age pasturalists, mounted on their horses, expanded from the Pontic and Caspian Steppes of Eurasia, into Europe around 5,000 years ago. But 1) it doesn't include any ANE (Ancient North Eurasian) component from the Mal'ta-Buret reference, and 2) it of course cannot distinguish it's Western Hunter-Gatherer reference from that inherited directly within Europe or elsewhere.
All that the FT-DNA Metal Age Invader reference appears to represent, is the population known as Caucasus Hunter-Gatherer. A minority component of Yamnaya DNA as we currently see it.
For the record, as the screendump above shows, my FT-DNA Ancient Origins are:
9% Metal Age Invader
47% Farmer
44% Hunter-Gatherer
0% Non European
Now that I've got that covered, I can move onto my next blog post, which I find more interesting - how I use My Ancient Origins to try to reconstruct my ancestry from 11,000 to 4,000 years ago.
Here I'm considering the third option to my enigma. My known ancestry is 100% English. However, autosomal DNA tests for Ancestry, by commercial companies, and by third party analysis, suggest that I have a mixture of European ancestries, including varying percentages of Southern European. I'm trying to best explain this phenomena. In previous posts, I considered 1) that my paper record is incomplete, or biologically incorrect. 2) that something ancient is picked up in analysis of present day English testers - that maybe reflect shared algorithms with ancient admixture, perhaps prehistoric, or Roman.
Now in this post, I consider the third option. That commercial DNA companies exaggerate their claims to be able to differentiate to any successful degree, between different regions of Europe in my ancestry. If this is indeed the case, it has significant repercussions for testers for example, in the USA, Canada, Australia, etc. If they have a poor paper trail, and poorly known ancestry, maybe it's all too easy for them to regard such DNA tests for ancestry, as indisputable and accurate truths.
Commercial DNA companies for Ancestry, are under pressure to supply to market demands. Their markets have been dominated particularly by USA customers. Some of them seasoned genealogists with good quality paper trails. Others, attracted by the easy option to know their ancestry before the, as 23andMe puts it, the Age of Migration before the past few centuries. Instead of spending a lifetime chasing documents, they can simply send a DNA sample to a company, and know their roots. People trust the science of DNA testing for ancestry. That is the demand that commercial companies can cater for.
But what if their abilities to accurately detect ancestry from Autosomal DNA is exaggerated?
My great grandfather Fred Smith, and my great Uncle Lenny.
This option supports the commercial DNA for ancestry companies claim, that I have Southern European ancestry. For this to be the case, my Southern European ancestors must have either a) been hidden in the gaps, the missing ancestors. b) be NPE (non parental events - biological ancestors that are contrary to recorded ancestors. Usually male). c) predate my genealogical record over the past 360 years or d) my recorded genealogy is faulty. I have badly researched my ancestry and have made mistakes.
What gaps are there? All of my generations are complete to and including my Generation 5. I have all of the names of my 16 direct ancestors at that generation (great great grandparents). All appear totally English, of English religious denominations. Their surnames and location were: Brooker of London (previously Oxfordshire), Shawers of London, Baxter of Norfolk, Barber of Norfolk, Smith of Norfolk, Peach of Norfolk, Barber (again) of Norfolk, Ellis of Norfolk, Curtis of Norfolk, Rose of Norfolk, Key of Norfolk, Goffen of Norfolk, Tammas-Tovell of Norfolk, Lawn of Norfolk, Thacker of Norfolk, and Daynes of Norfolk.
I have photographs of three of them.
Everything looks utterly English - the majority East Anglian.
The gaps start to appear at Generation 6 (G.G.G Grandparents) Three missing male ancestors - all missing fathers of illegitimate births. 29 out of 32 direct ancestors recorded though. All appear English again:
Brooker of Oxfordshire, Edney of Oxfordshire, Shawers of London, Durran of London (previously Oxfordshire), Baxter of Norfolk, Barber of Norfolk, Smith of Norfolk, Hewitt of Norfolk, Peach of Lincolnshire, Riches of Norfolk, Barber of Norfolk, Ellis of Norfolk, Goodram of Norfolk, Curtis of Norfolk, Larke of Norfolk, Rose of Norfolk, Barker of Norfolk, Key of Norfolk, Waters of Norfolk, Goffen of Norfolk, Nichols of Norfolk, Tovell of Norfolk, Tammas of Norfolk, Lawn of Norfolk, Springall of Norfolk, Thacker of Norfolk, Daynes of Norfolk, Quantrell of Norfolk. Oh, and a "Mary Ann" of Norfolk.
Again, all English, English religious denominations. Mainly rural working class East Anglian. No sign of any foreigners.
The record does start to really fall away at Generation 8. From then on, it's a minority of lines recorded, stretching back to the 1680's. However, at no where on my record of 207 direct ancestors, do I see anything that looks remotely non-English, never mind Southern European. No sign of any Catholicism anywhere.
Let's just consider percentages of DNA though.
Each grandparent gives me 25% on average.
Generation 3 (grandparent) 12.5%
Generation 4 (great grandparent) 6%
Generation 5 (great great grandparent) 3%
Generation 6 (G.G.G grandparent) 1.5%
Beyond then genetic recombination starts to really kick in, and you may have zero DNA from any particular ancestral lineage. It get's washed out. Only if it comes down from a number of lines is admixture highly likely to survive further back.
23andMe (V4 AC in spec after phasing with one parent) claims that both of my parents had 2% Southern European DNA. That takes it back to around MY Generation 6 or 7. Sure, I'm missing 9% of Generation 6, and 20% of Generation 7. My Southern European ancestors could have admixed then. But what are the chances of it happening on both sides? Possible, yes. I think unlikely though. No Southern European names or religions passed down. When was this? Around 1780 to 1820. Okay, if I want to piece national history into it, how about The Peninsular Wars (1807-1814)? The Royal Norfolk Regiment took an active part in that campaign. Could I have (presumably male) ancestors through both of my parents, that brought back Portuguese wives? It is a possibility. I'll acknowledge that. But am I weaving history in order to make it fit the DNA analysis?
FT-DNA (FF My Origins) claims that I have 32% "Southern European" ancestry. No sign of it in family history or photography. Too much likeness of recorded fathers. Okay, maybe it goes further back, but on multiple lines? I think that we are pushing this one. What is the chance of so many Southern Europeans given my above recorded or known English ancestry. It couldn't have happened.
DNA.land gives me 19% Southern European, including 13% Balkan. The same problem as the FT-DNA analysis. It just doesn't wash. It cannot fit.
Therefore I conclude:
That pretty much covers it for gaps, NPE's, etc. If any Southern European on the other hand, predates my genealogical record, then it would need to be on multiple lines, and to have lost all sign of Southern European surnames, religions, and traditions. I haven't seen any history of a mass Southern European migration to England 600 - 400 years ago.