Friday, 15 March 2013
Sense About Genealogical DNA Testing
I wrote last week about the new report from Sense About Science on the subject of Sense About Genetic Ancestry Testing. While I welcomed the publication of this report I was concerned at some of the inaccurate media coverage it generated which gave the false impression that all genetic ancestry testing is "meaningless". The report made it quite clear that DNA testing can be legitimately used for genealogical purposes, but this aspect was overlooked in some of the newspaper articles who quoted from the report out of context. I was very pleased, therefore, that Sense About Science invited me to write a guest blog post for them to help set the record straight. The post, entitled Sense About Genealogical DNA testing, is now live on the Sense About Science website. I am very grateful to all the geneticists and genetic genealogists who provided useful feedback which resulted in a much better article than I would ever have written on my own.
Friday, 8 March 2013
Sense About Genetic Ancestry Testing
The UK press has been flooded in the last year or so with stories about a number of people, including a few celebrities, who who have had their DNA tested and who have been told extraordinary stories about their ancestry. The Guardian reported that the actor Tom Conti is directly related to Napoleon Bonaparte. The Scottish comedian Fred MacAulay was told on BBC Radio Scotland that his dad's Y-chromosome DNA "put him in south-west Ireland as part of the descent of Irish kings who were captured by Vikings and then sold in the slave market taking him up to the Hebrides". The Daily Mail revealed that a Scottish pensioner by the name of Ian Kinnaird learnt from his mitochondrial DNA test that he is "the grandfather of everyone in Britain". While the BBC and the national press have uncritically lapped up these stories and published them without question unfortunately they contain many errors and exaggerations.
As genetic genealogists we normally use DNA as a tool to help with our genealogical research. However, DNA testing can also provide some insight into one's deep ancestry. A man can take a Y-chromosome DNA test to explore his ancestry on the direct paternal line. Both men and women can take a mitochondrial DNA test to explore their ancestry on the direct maternal line. When you receive your Y-DNA or mtDNA results you are given a haplogroup assignment. The haplogroup represents your branch on the human Y-DNA or mtDNA family tree. Haplogroups are defined by markers known as SNPs (single-nucleotide polymorphisms) - small changes in the letters of the DNA alphabet. The Y-DNA tree is maintained by ISOGG - the International Society of Genetic Genealogy - and can be found here. The mitochondrial DNA tree is maintained by Mannis van Oven from the University Medical Center in Rotterdam in the Netherlands and can be found on the Phylotree website.
Haplogroups do tend to cluster in specific geographical regions and attempts can be made to explore the origins of these haplogroups by looking at their distribution and diversity in present-day populations, but there are inherent biases in the available databases, nowhere enough samples have been obtained and sometimes the conclusions drawn are highly speculative. Nevertheless many scientific papers have been published in peer-reviewed scientific journals on the origins of the different haplogroups, but with the discovery of more new markers on an almost daily basis these studies can often become out of date as soon as they are published. It can, of course, be fun to see who else shares your haplogroup. There is a page on Wikipedia which provides a list of the haplogroups of historical and famous figures, and there is also a famous DNA page on the ISOGG website. However, the markers that define these haplogroups often arose many thousands of years ago so it is therefore somewhat meaningless to declare, for example, that Tom Conti is directly related to Napoleon when they only share a common ancestor from several thousand years ago on their direct paternal line and they share that ancestor in common with thousands of other men in the same haplogroup. A DNA test cannot tell you that you are descended from a slave who was captured by the Vikings, and it is quite preposterous to tell someone that he is the ''grandfather of everyone in Britain" for many reasons not the least of which is that this ridiculous claim was based on a mitochondrial DNA test and males cannot pass on mtDNA to their children!
To counter some of these outlandish claims and to help the public to understand the issues involved the charity Sense About Science has produced a very useful new booklet entitled Sense About Genetic Ancestry Testing which can be downloaded from their website. The booklet has been written by a number of distinguished geneticists and explains very clearly the problems of assigning ancestry from a DNA test. Unfortunately some of the reports in the newspapers and online have commented on the publication of this booklet and given the story a somewhat misleading slant. The Telegraph has, for example, declared that "DNA tests [are] branded 'meaningless'" while the BBC more cautiously warns that "Some DNA ancestry services [are] akin to 'genetic astrology'". It is important to note that these headlines apply only to certain deep ancestry tests and not to the tests that we use for our genealogical research. As the Sense About Science authors note in their report:
If you wish to get your DNA tested either for genealogical purposes or to explore your deep ancestry there are a range of companies to choose from. The ISOGG Wiki has many valuable resources including a number of charts comparing the offerings of the various testing companies. Whatever your reason for taking a DNA test you will get the best value for your money if you choose a company which provides a genealogical matching database where you can contact your matches and get involved in projects. The two companies that I recommend are Family Tree DNA and 23andMe. Family Tree DNA host all of my DNA projects. They offer the widest range of tests and have by far the largest genetic genealogy database. They have over 7300 surname projects, a large number of geographical projects as well as projects for all the Y-DNA and mtDNA haplogroups. The 23andMe test is essentially a health and traits test but it also provides haplogroup assignments and it includes a cousin-matching service, known as Relative Finder, based on autosomal DNA. If you are interested in the 23andMe test you can read my reviews here.
As genetic genealogists we normally use DNA as a tool to help with our genealogical research. However, DNA testing can also provide some insight into one's deep ancestry. A man can take a Y-chromosome DNA test to explore his ancestry on the direct paternal line. Both men and women can take a mitochondrial DNA test to explore their ancestry on the direct maternal line. When you receive your Y-DNA or mtDNA results you are given a haplogroup assignment. The haplogroup represents your branch on the human Y-DNA or mtDNA family tree. Haplogroups are defined by markers known as SNPs (single-nucleotide polymorphisms) - small changes in the letters of the DNA alphabet. The Y-DNA tree is maintained by ISOGG - the International Society of Genetic Genealogy - and can be found here. The mitochondrial DNA tree is maintained by Mannis van Oven from the University Medical Center in Rotterdam in the Netherlands and can be found on the Phylotree website.
Haplogroups do tend to cluster in specific geographical regions and attempts can be made to explore the origins of these haplogroups by looking at their distribution and diversity in present-day populations, but there are inherent biases in the available databases, nowhere enough samples have been obtained and sometimes the conclusions drawn are highly speculative. Nevertheless many scientific papers have been published in peer-reviewed scientific journals on the origins of the different haplogroups, but with the discovery of more new markers on an almost daily basis these studies can often become out of date as soon as they are published. It can, of course, be fun to see who else shares your haplogroup. There is a page on Wikipedia which provides a list of the haplogroups of historical and famous figures, and there is also a famous DNA page on the ISOGG website. However, the markers that define these haplogroups often arose many thousands of years ago so it is therefore somewhat meaningless to declare, for example, that Tom Conti is directly related to Napoleon when they only share a common ancestor from several thousand years ago on their direct paternal line and they share that ancestor in common with thousands of other men in the same haplogroup. A DNA test cannot tell you that you are descended from a slave who was captured by the Vikings, and it is quite preposterous to tell someone that he is the ''grandfather of everyone in Britain" for many reasons not the least of which is that this ridiculous claim was based on a mitochondrial DNA test and males cannot pass on mtDNA to their children!
To counter some of these outlandish claims and to help the public to understand the issues involved the charity Sense About Science has produced a very useful new booklet entitled Sense About Genetic Ancestry Testing which can be downloaded from their website. The booklet has been written by a number of distinguished geneticists and explains very clearly the problems of assigning ancestry from a DNA test. Unfortunately some of the reports in the newspapers and online have commented on the publication of this booklet and given the story a somewhat misleading slant. The Telegraph has, for example, declared that "DNA tests [are] branded 'meaningless'" while the BBC more cautiously warns that "Some DNA ancestry services [are] akin to 'genetic astrology'". It is important to note that these headlines apply only to certain deep ancestry tests and not to the tests that we use for our genealogical research. As the Sense About Science authors note in their report:
"There are credible ways to use the genetic data from mtDNA or Y chromosomes in individual ancestry testing, such as to supplement independent, historical studies of genealogy. If, for example, two men have identified – through historical research, possibly involving surnames – a common maleline ancestor in the sixteenth century, it would be reasonable to use their Y chromosome data to test this. There are some ancestry testing companies that offer this service."I hope that lessons will have been learnt as a result of the Sense About Science publication and that the hyperbole of recent months will not be repeated. It is perhaps too much to hope that the press will take a more responsible attitude and will only publish stories based on scientific research published in peer-reviewed scientific journals rather than rehashing sensational stories from press releases submitted by PR companies as publicity stunts. In the meantime I would urge everyone to heed the words of Professor David Balding on the Sense About Science website: "Be wary of news items about genetic history - that someone famous is related to the Queen of Sheba or a Roman soldier. Often these come from PR material provided by genetic testing companies and can be trivial, exaggerated or just plain wrong."
If you wish to get your DNA tested either for genealogical purposes or to explore your deep ancestry there are a range of companies to choose from. The ISOGG Wiki has many valuable resources including a number of charts comparing the offerings of the various testing companies. Whatever your reason for taking a DNA test you will get the best value for your money if you choose a company which provides a genealogical matching database where you can contact your matches and get involved in projects. The two companies that I recommend are Family Tree DNA and 23andMe. Family Tree DNA host all of my DNA projects. They offer the widest range of tests and have by far the largest genetic genealogy database. They have over 7300 surname projects, a large number of geographical projects as well as projects for all the Y-DNA and mtDNA haplogroups. The 23andMe test is essentially a health and traits test but it also provides haplogroup assignments and it includes a cousin-matching service, known as Relative Finder, based on autosomal DNA. If you are interested in the 23andMe test you can read my reviews here.
WDYTYA Live Day 3 Part 2: The new ancient root of the Y-tree
Sunday is always the quietest day at WDYTYA and in a lull at the end of the day I took the opportunity to listen to a fascinating talk by Dr Michael Hammer from the University of Arizona on "DNA and our ancestral origins". The talk began with an explanation of the two different models of human evolution - the Out of Africa replacement model and the multiregional model. Hammer discussed the important work of Svaante Pääbo from the Max Planck Institute who has sequenced the Neanderthal and Denisovan genomes. All non-Africans carry traces of Neanderthal DNA. Small percentages of Denisovan DNA are found today only in populations in Melanesia. I have been surprised to see that most of the people who have taken the new Geno 2.0 test from the Genographic Project have reported receiving small percentages of Denisovan DNA, despite having ancestors who lived in Europe and not Melanesia. These figures can be seen in this thread on the Genealogy DNA mailing list. I asked Michael Hammer why this should be the case, and he suggested that these results must surely be in error. It is very difficult to detect introgression and the DNA that is being assigned as Denisovan is probably ancient DNA indicative of ancient shared ancestry between humans, Denisovans and Neanderthals rather than genuine Denisovan DNA. The X-chromosome provides further insight into our ancient origins and intriguingly a haplotree constructed from part of the X-chromosome shows that the most recent common ancestor on our X-chromosome line traces back not to Africa but to Asia, and the TMRCA (time to the most recent common ancestor) is around two million years ago.
However, for genetic genealogists by far the most exciting part of Michael Hammer's talk was the story of the discovery of the new ancient root of the human Y-chromosome tree, which had first been announced to a select audience at the Family Tree DNA group administrators' conference in November 2012. The most extraordinary part of the story is that it was a citizen science discovery. An African American gentleman in South Carolina submitted a sample of his DNA to National Geographic's Genographic Project. He subsequently transferred his Y-DNA results to Family Tree DNA where he joined the haplogroup A project. Bonnie Schrack, the very astute administrator of the haplogroup A project, noticed that FTDNA had not been able to assign a haplogroup to the sample. She decided to take matters into her own hands and raised some money so that the Y-chromosome could be sequenced as part of the Walk through the Y programme run by Thomas Krahn, FTDNA's chief Y-chromosome scientist. It proved impossible to place the sequence on the Y-tree as all the SNP markers were ancestral, but there were also many new SNPs found in the sample. The challenge was then to determine precisely where the sample belonged on the tree as it fell outside the range of all known Y-chromosome lineages. Additional sequencing was done on chimps and gorillas for comparison purposes, and it was eventually determined that the sequence defined a new root of the Y-tree dating back around 338,000 years before present. The new root was given the name of haplogroup A00 leaving room for the possibility that additional divergent lineages might one day be discovered and it would then be a simple matter of adding additional zeros.
The research was published on 28th February in the American Journal of Human Genetics in an article entitled An African American Paternal Lineage Adds an Extremely Ancient Root to the Human Y Chromosome Phylogenetic Tree. The official press release from the University of Arizona can be read here. CeCe Moore, who attended the FTDNA conference, provides further details on her blog. The paper concludes with the following sentence: "Finally, the discovery of the A00 lineage demonstrates the power of public participation in the scientific process — a venture that is likely to continue in the current era of personal genomics." We have only captured a tiny fraction of the genetic diversity of the world at present. I wonder how many more exciting discoveries are waiting to be made as more people start to get their DNA tested and as more samples are tested from around the world and particularly in Africa. We can also expect many of these discoveries to be made by citizen scientists working as volunteer project administrators at commercial genetic genealogy testing companies.
There was so much going on at WDYTYA that unfortunately I did not have time to visit all the stands. I had wanted to ask Ancestry if they had any plans to launch their autosomal DNA test outside the US. Luckily David Hollister, a fellow member of the Guild of One-Name Studies, was able to have a word with them. He reported that they are not yet ready to launch their test outside the US for the following reasons:
- Complicated EEC Regulations.
- Probably not enough profit in it.
- Labs are too busy
David subsequently made further enquiries with Ancestry and was told by Karen Richardson, their Senior Manager for Community Marketing, that there is no definitive answer on the launch of the DNA test in the UK though "there is the hope that it might be in 2014, but we can't guarantee that".
The day ended at 4.30 pm, and it was then time to pack up the stands and head home. Max Blankfeld, FTDNA's Vice President of Marketing, had two enormous bags full of DNA swabs to take back with him to Houston, Texas. The company sold a record number of kits at WDYTYA this year. These samples are now starting to be processed. I have already had two new people join my Devon DNA Project who tested at WDYTYA, and I shall look forward to receiving their results in the next couple of months.
See also
- Who Do You Think You Are? Live 2013 Days 1 and 2
- Who Do You Think You Are? Live Day 3: Alistair Moffat on how DNA is rewriting British history
However, for genetic genealogists by far the most exciting part of Michael Hammer's talk was the story of the discovery of the new ancient root of the human Y-chromosome tree, which had first been announced to a select audience at the Family Tree DNA group administrators' conference in November 2012. The most extraordinary part of the story is that it was a citizen science discovery. An African American gentleman in South Carolina submitted a sample of his DNA to National Geographic's Genographic Project. He subsequently transferred his Y-DNA results to Family Tree DNA where he joined the haplogroup A project. Bonnie Schrack, the very astute administrator of the haplogroup A project, noticed that FTDNA had not been able to assign a haplogroup to the sample. She decided to take matters into her own hands and raised some money so that the Y-chromosome could be sequenced as part of the Walk through the Y programme run by Thomas Krahn, FTDNA's chief Y-chromosome scientist. It proved impossible to place the sequence on the Y-tree as all the SNP markers were ancestral, but there were also many new SNPs found in the sample. The challenge was then to determine precisely where the sample belonged on the tree as it fell outside the range of all known Y-chromosome lineages. Additional sequencing was done on chimps and gorillas for comparison purposes, and it was eventually determined that the sequence defined a new root of the Y-tree dating back around 338,000 years before present. The new root was given the name of haplogroup A00 leaving room for the possibility that additional divergent lineages might one day be discovered and it would then be a simple matter of adding additional zeros.
There was so much going on at WDYTYA that unfortunately I did not have time to visit all the stands. I had wanted to ask Ancestry if they had any plans to launch their autosomal DNA test outside the US. Luckily David Hollister, a fellow member of the Guild of One-Name Studies, was able to have a word with them. He reported that they are not yet ready to launch their test outside the US for the following reasons:
- Complicated EEC Regulations.
- Probably not enough profit in it.
- Labs are too busy
David subsequently made further enquiries with Ancestry and was told by Karen Richardson, their Senior Manager for Community Marketing, that there is no definitive answer on the launch of the DNA test in the UK though "there is the hope that it might be in 2014, but we can't guarantee that".
The day ended at 4.30 pm, and it was then time to pack up the stands and head home. Max Blankfeld, FTDNA's Vice President of Marketing, had two enormous bags full of DNA swabs to take back with him to Houston, Texas. The company sold a record number of kits at WDYTYA this year. These samples are now starting to be processed. I have already had two new people join my Devon DNA Project who tested at WDYTYA, and I shall look forward to receiving their results in the next couple of months.
See also
- Who Do You Think You Are? Live 2013 Days 1 and 2
- Who Do You Think You Are? Live Day 3: Alistair Moffat on how DNA is rewriting British history
Friday, 1 March 2013
Who Do You Think You Are? Live Day 3: Alistair Moffat on how DNA is rewriting British history
On Sunday I arrived early at Olympia and in the quiet time before the doors opened to the public I managed to call in at the stand of the History Press, who are the publishers of my two books. They told me that they had already sold all their copies of DNA and Social Networking and that they only had four copies left of my Surnames Handbook. Fortunately the Guild of One-Name Studies still had a few copies left on their stall so I hope no one was disappointed. I picked up from the History Press stand a copy of the book by John Ashdown Hill entitled The Last Days of Richard III and the Fate of His DNA: The Book that Inspired the Dig. In this book the author describes the detailed research he carried out on the family tree of Richard III in the search for a female line descendant of one of Richard's siblings who would be a candidate for mitochondrial DNA testing.
I was very pleased to see Family Historian exhibiting at WDYTYA for the first time this year. I use this excellent software for my own family history research and it has now developed a very loyal and dedicated user base. I had a brief chat with Jackie Depelle who was helping on the Family Historian stand. Jackie is a fellow member of the Guild of One-Name Studies. She teaches family history classes in Yorkshire and also teaches courses on the use of the software. Jackie told me that there had been a lot of interest in Family Historian, and that many others users had also come to the stand to say hello.
Sunday is traditionally the quietest day at WDYTYA, but my talk in the morning was again packed out with people having to stand at the back. All the volunteers on the Family Tree DNA and ISOGG stands were kept busy throughout the day explaining to people how DNA testing works and selling many more kits.
At lunchtime I attended the talk by Alistair Moffat on "How DNA is rewriting British history". The research had been heralded in a story in the Daily Telegraph on the previous Friday entitled One million Brits 'descended from Romans' with a promise that the figures behind the study would be announced by Alistair Moffat at Who Do You Think You Are? Unfortunately the talk was a big disappointment. Alistair Moffat did not use any slides and read his lecture from a script. He started with a brief explanation of the Y-chromosome and mitochondrial DNA markers which are used in deep ancestry studies. He did not say so but these markers are technically known as SNPs (pronounced "snips") which is short for single-nucleotide polymorphisms. Moffat explained that he would provide one detailed example in his lecture to explain how DNA is helping to rewrite British history and made the surprise announcement that his company BritainsDNA (which also trades as ScotlandsDNA, IrelandsDNA, and YorkshiresDNA) has found the lost Roman legions. The historians and scientists at BritainsDNA have supposedly discovered through DNA testing that around one million men in Britain can claim to be the direct descendants in the male line of the Roman legions. Unfortunately, he failed to provide any scientific evidence to back up these extraordinary claims.
The bulk of the talk consisted of a lesson on Roman history and the Roman occupation of Britain. Moffat estimates that there were perhaps two million people living in England and Wales when the Romans invaded. He speculated that around 40,000 Roman soldiers and cavalrymen were stationed in Britain. It seems reasonable to suppose that the Y-chromosome of some of these Roman soldiers and cavalrymen has survived in the Y-chromosome DNA of living male-line descendants but proving this link is a somewhat different matter. Moffat stated that before the middle of the second century AD recruitment to the Roman army was restricted to men who were Roman citizens and who were therefore Italians or of Italian descent. He suggested that a comparison between Italian Y-chromosome DNA and British Y-chromosome DNA might show up something of the genetic legacy of the Roman legions. As Ireland was never conquered by the Romans and the south of Scotland was only occupied for a short time Roman DNA ought be present in England and Wales, absent in Ireland and should occur only at low frequencies in Scotland. As he rightly pointed out, there are many caveats to this argument. DNA often arrived in Italy from elsewhere, and of course the Roman Army did not consist entirely of Italians. He cited the example of the Sarmatian cavalry who were from what is now Romania and who were stationed at Ribchester Fort in Lancashire. (I may have misheard at this point because the Wikipedia article on the Sarmatians suggest that they are from Iran and not Romania.)
No details were given on how many DNA samples were used in the study in Britain and Italy. BritainsDNA is a commercial DNA testing company and is reliant on customers paying money to order a DNA test. It is therefore very important to ensure that the samples used are from a random selection of the population. No details were given as to how the samples were randomised to take into account biases in the customer base. The conclusion that around one million British men are descended from the lost Roman legions was based purely on the finding of five of the rarer haplogroups in the samples studied. The five haplogroups that supposedly represent the Roman legions are given below. I have used the marker names given by Moffat but have provided in square brackets the haplogroup names based on the current ISOGG Y-SNP tree and the alternative SNP names where a more familiar name is normally used as BritainsDNA has its own proprietary naming system for some SNPs.
The first haplogroup associated by Moffat with Roman ancestry is R1b-S28 [R1b-U152 or haplogroup R1b1a2a1a1b2]. According to Moffat this marker is known as the Alpine marker. It occurs at a frequency of 13% in Italy, 6.5% in England and Wales, 4.3% in Scotland and 1.8% in Ireland. At this point Moffat's evidence was somewhat contradictory as he told us that this marker almost certainly arrived in Britain around 3000 BC and that it might have been the marker of the Amesbury Archer. However, he then suggested that this marker is also a candidate for Roman ancestry because of its high frequency in Italy, its presence in England and Wales and its lower frequency or complete absence in areas that were not occupied by the Romans or only briefly occupied. He did not explain how it was possible to differentiate between indigeneous U152 and U152 supposedly brought to England by the Romans. Nevertheless, extrapolating from figures from the 2011 census, he went on to estimate that 1.6 million British men are U152/S28. I missed the next point but there was an additional calculation which substantially reduced the original estimate to produce the claim that half a million men in England and Wales are descended from Roman soldiers simply because they are U152/S28.
Moffat went on to claim that four additional Y-chromosome DNA markers arrived with the Romans. These are:
1) E-V13 [haplogroup E1b1b1a1b - known by BritainsDNA as the "Balkan group"]
2) G-S314 [G-M201 is haplogroup G and is known by BritainsDNA as "Ancient Caucasian"]
3) J-M172 [haplogroup J2 known by BritainsDNA as the "Herdsman Farmers"]. Moffat claimed that a subgroup of J-M172, known as J-M67 [haplogroup J2a1b] is particularly Italian.
4) R1b-M269* [this group is known by BritainsDNA as the "Anatolian group". The asterisk normally denotes that someone has tested negative for all downstream M269 markers. There are now numerous R1b subclades but the full list of markers tested by BritainsDNA is not known.]
These four haplogroups are supposed to add another 2.3 million Englishmen and Welshmen who can trace their Y-chromosome lines to the Romans. For some reason which I did not understand Moffat than took other factors into account and reduced the numbers to produce a total of one million English and Welsh men in his study who supposedly have Roman ancestry, corresponding with the headline figure cited in the Daily Telegraph article. Unfortunately no explanation was given as to why these four haplogroups in particular should be associated with Roman ancestry. All the base haplogroups are very widespread and it's only when you drill right down to the more recent subclades that you start to see more refined geographical distributions. Haplogroup G, for example, is found throughout Europe but is also found in parts of Asia and Africa. The haplogroup G project at Family Tree DNA has a huge collection of around 3000 haplogroup G samples from all over the world which have been placed in sub-groups based on advanced SNP testing. Some of these subgroups have only been found in specific countries or regions such as Spain, Turkey or the Middle East, but the numbers tested within each subgroup are still relatively small and it is far too early to draw any conclusions. Numerous scientific papers have been written on haplogroup G and its subclades, often coming to very different conclusions. Many of these scientific papers are linked in the haplogroup G article on Wikipedia. Without doing additional SNP testing to define the subclades and without the aid of Y-STR markers to predict the subclade it would seem impossible to conclude that the presence of haplogroup G on its own is a sign of Roman ancestry. Even then, other evidence would need to be taken into account such as the archaeological evidence and ancient DNA analysis. Furthermore, present-day Italians belong to a wide variety of haplogroups, most of which are also found in the British Isles. A quick glance at the results of the large Italy DNA Project at Family Tree DNA gives a rough idea of the present-day haplogroup distribution in Italy. No reason was given as to why a few haplogroups were selected seemingly at random from the wide range of haplogroups found in Italy today to represent Roman ancestry.
After the announcement of the five markers that are supposedly associated with the lost Roman legions there then followed a brief discussion about a new marker by the name of R1b-S190 [haplogroup R1b1a2a1a1b3a7d1] which was discovered by Dr Jim Wilson in 2012. This marker is apparently found in about 1% of Scottish men and is particularly prevalent in just a few parts of Scotland. It is also found at low frequencies in Ireland. According to Moffat this marker is associated with descent from the Maeatae, though this claim was based purely on the evidence of the present-day distribution in Scotland in an undisclosed number of samples.
DNA testing is a very effective tool for family history when used in conjunction with the traditional documentary research. However, at the deep ancestry level there are inherent problems in associating particular types of DNA with Roman legions, the Vikings, the Celts, the Normans, the Maeatae or any other ethnic group. The problems are well described in an excellent article "To claim someone has 'Viking ancestors' is no better than astrology" written by Mark Thomas, Professor of Evolutionary Genetics at University College London, for The Guardian. As Professor Thomas notes, it is important that scientific research is published in peer-reviewed scientific journals. The system is not perfect but it does at least ensure that basic standards are followed and it lends a degree of credibility to the research. The Sense About Science website has a very useful new booklet entitled Peer Review Matters to the Public, which explains why the peer review process is so important, and I recommend that anyone wishing to know more about the subject should read this booklet.
Unfortunately in the case of this Roman research it appears that it is not to be published in a scientific journal but will instead bypass the usual peer review process and will be published in a new book written by Alistair Moffat and his business partner Dr James Wilson entitled The British: A Genetic Journey which is due out in September. It therefore looks as though we will have to wait for publication of the book to find out more about the sampling process and how these conclusions have been reached.
The next lecture I attended on Sunday was a fascinating talk by Dr Michael Hammer on "DNA and our ancestral origins" which included news on an amazing citizen science discovery. Michael Hammer is the Associate Professor and Research Scientist at the Hammer Lab at the University of Arizona and Family Tree DNA's Chief Scientist. I shall write about his lecture in my next blog post.
Further information
For details on the Y-chromosome DNA tests offered by the various DNA testing companies see the Y-DNA testing comparison chart in the ISOGG Wiki. Note that for genealogical matching purposes it is necessary to order from a company which tests Y-STR markers. Y-SNP markers can only be used for deep ancestry purposes.
See also
- Who Do You Think You Are? Live 2013 Days 1 and 2
- Who Do You Think You Are? Live Day 3 Part 2: The new ancient root of the Y-tree
© 2013 Debbie Kennett
I was very pleased to see Family Historian exhibiting at WDYTYA for the first time this year. I use this excellent software for my own family history research and it has now developed a very loyal and dedicated user base. I had a brief chat with Jackie Depelle who was helping on the Family Historian stand. Jackie is a fellow member of the Guild of One-Name Studies. She teaches family history classes in Yorkshire and also teaches courses on the use of the software. Jackie told me that there had been a lot of interest in Family Historian, and that many others users had also come to the stand to say hello.
Sunday is traditionally the quietest day at WDYTYA, but my talk in the morning was again packed out with people having to stand at the back. All the volunteers on the Family Tree DNA and ISOGG stands were kept busy throughout the day explaining to people how DNA testing works and selling many more kits.
At lunchtime I attended the talk by Alistair Moffat on "How DNA is rewriting British history". The research had been heralded in a story in the Daily Telegraph on the previous Friday entitled One million Brits 'descended from Romans' with a promise that the figures behind the study would be announced by Alistair Moffat at Who Do You Think You Are? Unfortunately the talk was a big disappointment. Alistair Moffat did not use any slides and read his lecture from a script. He started with a brief explanation of the Y-chromosome and mitochondrial DNA markers which are used in deep ancestry studies. He did not say so but these markers are technically known as SNPs (pronounced "snips") which is short for single-nucleotide polymorphisms. Moffat explained that he would provide one detailed example in his lecture to explain how DNA is helping to rewrite British history and made the surprise announcement that his company BritainsDNA (which also trades as ScotlandsDNA, IrelandsDNA, and YorkshiresDNA) has found the lost Roman legions. The historians and scientists at BritainsDNA have supposedly discovered through DNA testing that around one million men in Britain can claim to be the direct descendants in the male line of the Roman legions. Unfortunately, he failed to provide any scientific evidence to back up these extraordinary claims.
The bulk of the talk consisted of a lesson on Roman history and the Roman occupation of Britain. Moffat estimates that there were perhaps two million people living in England and Wales when the Romans invaded. He speculated that around 40,000 Roman soldiers and cavalrymen were stationed in Britain. It seems reasonable to suppose that the Y-chromosome of some of these Roman soldiers and cavalrymen has survived in the Y-chromosome DNA of living male-line descendants but proving this link is a somewhat different matter. Moffat stated that before the middle of the second century AD recruitment to the Roman army was restricted to men who were Roman citizens and who were therefore Italians or of Italian descent. He suggested that a comparison between Italian Y-chromosome DNA and British Y-chromosome DNA might show up something of the genetic legacy of the Roman legions. As Ireland was never conquered by the Romans and the south of Scotland was only occupied for a short time Roman DNA ought be present in England and Wales, absent in Ireland and should occur only at low frequencies in Scotland. As he rightly pointed out, there are many caveats to this argument. DNA often arrived in Italy from elsewhere, and of course the Roman Army did not consist entirely of Italians. He cited the example of the Sarmatian cavalry who were from what is now Romania and who were stationed at Ribchester Fort in Lancashire. (I may have misheard at this point because the Wikipedia article on the Sarmatians suggest that they are from Iran and not Romania.)
No details were given on how many DNA samples were used in the study in Britain and Italy. BritainsDNA is a commercial DNA testing company and is reliant on customers paying money to order a DNA test. It is therefore very important to ensure that the samples used are from a random selection of the population. No details were given as to how the samples were randomised to take into account biases in the customer base. The conclusion that around one million British men are descended from the lost Roman legions was based purely on the finding of five of the rarer haplogroups in the samples studied. The five haplogroups that supposedly represent the Roman legions are given below. I have used the marker names given by Moffat but have provided in square brackets the haplogroup names based on the current ISOGG Y-SNP tree and the alternative SNP names where a more familiar name is normally used as BritainsDNA has its own proprietary naming system for some SNPs.
The first haplogroup associated by Moffat with Roman ancestry is R1b-S28 [R1b-U152 or haplogroup R1b1a2a1a1b2]. According to Moffat this marker is known as the Alpine marker. It occurs at a frequency of 13% in Italy, 6.5% in England and Wales, 4.3% in Scotland and 1.8% in Ireland. At this point Moffat's evidence was somewhat contradictory as he told us that this marker almost certainly arrived in Britain around 3000 BC and that it might have been the marker of the Amesbury Archer. However, he then suggested that this marker is also a candidate for Roman ancestry because of its high frequency in Italy, its presence in England and Wales and its lower frequency or complete absence in areas that were not occupied by the Romans or only briefly occupied. He did not explain how it was possible to differentiate between indigeneous U152 and U152 supposedly brought to England by the Romans. Nevertheless, extrapolating from figures from the 2011 census, he went on to estimate that 1.6 million British men are U152/S28. I missed the next point but there was an additional calculation which substantially reduced the original estimate to produce the claim that half a million men in England and Wales are descended from Roman soldiers simply because they are U152/S28.
Moffat went on to claim that four additional Y-chromosome DNA markers arrived with the Romans. These are:
1) E-V13 [haplogroup E1b1b1a1b - known by BritainsDNA as the "Balkan group"]
2) G-S314 [G-M201 is haplogroup G and is known by BritainsDNA as "Ancient Caucasian"]
3) J-M172 [haplogroup J2 known by BritainsDNA as the "Herdsman Farmers"]. Moffat claimed that a subgroup of J-M172, known as J-M67 [haplogroup J2a1b] is particularly Italian.
4) R1b-M269* [this group is known by BritainsDNA as the "Anatolian group". The asterisk normally denotes that someone has tested negative for all downstream M269 markers. There are now numerous R1b subclades but the full list of markers tested by BritainsDNA is not known.]
These four haplogroups are supposed to add another 2.3 million Englishmen and Welshmen who can trace their Y-chromosome lines to the Romans. For some reason which I did not understand Moffat than took other factors into account and reduced the numbers to produce a total of one million English and Welsh men in his study who supposedly have Roman ancestry, corresponding with the headline figure cited in the Daily Telegraph article. Unfortunately no explanation was given as to why these four haplogroups in particular should be associated with Roman ancestry. All the base haplogroups are very widespread and it's only when you drill right down to the more recent subclades that you start to see more refined geographical distributions. Haplogroup G, for example, is found throughout Europe but is also found in parts of Asia and Africa. The haplogroup G project at Family Tree DNA has a huge collection of around 3000 haplogroup G samples from all over the world which have been placed in sub-groups based on advanced SNP testing. Some of these subgroups have only been found in specific countries or regions such as Spain, Turkey or the Middle East, but the numbers tested within each subgroup are still relatively small and it is far too early to draw any conclusions. Numerous scientific papers have been written on haplogroup G and its subclades, often coming to very different conclusions. Many of these scientific papers are linked in the haplogroup G article on Wikipedia. Without doing additional SNP testing to define the subclades and without the aid of Y-STR markers to predict the subclade it would seem impossible to conclude that the presence of haplogroup G on its own is a sign of Roman ancestry. Even then, other evidence would need to be taken into account such as the archaeological evidence and ancient DNA analysis. Furthermore, present-day Italians belong to a wide variety of haplogroups, most of which are also found in the British Isles. A quick glance at the results of the large Italy DNA Project at Family Tree DNA gives a rough idea of the present-day haplogroup distribution in Italy. No reason was given as to why a few haplogroups were selected seemingly at random from the wide range of haplogroups found in Italy today to represent Roman ancestry.
After the announcement of the five markers that are supposedly associated with the lost Roman legions there then followed a brief discussion about a new marker by the name of R1b-S190 [haplogroup R1b1a2a1a1b3a7d1] which was discovered by Dr Jim Wilson in 2012. This marker is apparently found in about 1% of Scottish men and is particularly prevalent in just a few parts of Scotland. It is also found at low frequencies in Ireland. According to Moffat this marker is associated with descent from the Maeatae, though this claim was based purely on the evidence of the present-day distribution in Scotland in an undisclosed number of samples.
DNA testing is a very effective tool for family history when used in conjunction with the traditional documentary research. However, at the deep ancestry level there are inherent problems in associating particular types of DNA with Roman legions, the Vikings, the Celts, the Normans, the Maeatae or any other ethnic group. The problems are well described in an excellent article "To claim someone has 'Viking ancestors' is no better than astrology" written by Mark Thomas, Professor of Evolutionary Genetics at University College London, for The Guardian. As Professor Thomas notes, it is important that scientific research is published in peer-reviewed scientific journals. The system is not perfect but it does at least ensure that basic standards are followed and it lends a degree of credibility to the research. The Sense About Science website has a very useful new booklet entitled Peer Review Matters to the Public, which explains why the peer review process is so important, and I recommend that anyone wishing to know more about the subject should read this booklet.
Unfortunately in the case of this Roman research it appears that it is not to be published in a scientific journal but will instead bypass the usual peer review process and will be published in a new book written by Alistair Moffat and his business partner Dr James Wilson entitled The British: A Genetic Journey which is due out in September. It therefore looks as though we will have to wait for publication of the book to find out more about the sampling process and how these conclusions have been reached.
The next lecture I attended on Sunday was a fascinating talk by Dr Michael Hammer on "DNA and our ancestral origins" which included news on an amazing citizen science discovery. Michael Hammer is the Associate Professor and Research Scientist at the Hammer Lab at the University of Arizona and Family Tree DNA's Chief Scientist. I shall write about his lecture in my next blog post.
Further information
For details on the Y-chromosome DNA tests offered by the various DNA testing companies see the Y-DNA testing comparison chart in the ISOGG Wiki. Note that for genealogical matching purposes it is necessary to order from a company which tests Y-STR markers. Y-SNP markers can only be used for deep ancestry purposes.
See also
- Who Do You Think You Are? Live 2013 Days 1 and 2
- Who Do You Think You Are? Live Day 3 Part 2: The new ancient root of the Y-tree
© 2013 Debbie Kennett
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