Ancestry.com Continues to Be Best In Class for DNA Ancestry Ethnic Composition

I've been very kind to 23andme in the past because of it's easy-to-use interface and it's candor when it comes to disclosing the weaknesses in its algorithm.  Nothing was worse than the other testing companies representing to people that their ethnic calculators were accurate, only to discover that the science was really just a guess.  Many authors have written entire chapters in books (this one quite funny!) that discuss these concepts.

But as 23andme prepares for its exciting and certainly in-demand upcoming IPO, it needs an update.  It needs to offer X chromosome searching, for one example.  

 And it's DNA ancestry has been lapped now, twice, by Ancestry.com.  Ancestry.com, who we've been harsh on before, now features INCREDIBLY accurate DNA ancestry estimates.  To tell you how far they've come, so fast, it'd be like going from horse and buggy to the space shuttle.  Their new tool is that accurate.

One user wrote me who hired a genealogist to complete a full pedigree.  That's 64 ancestors!  That user has a complete 64 ancestor pedigree now, well-documented with church and family records.  Of her 64 ancestors, 62 come from northeast Bavaria in Germany, 1 comes from Sweden, and 1 from the Czech Republic.  In other words, she's 96.8% German, from the Bavarian forest, and she's about 1.56% Swedish and Czech.

She got her ancestry results from Ancestry.com, and would you believe it said she is 96% German, from the Bavarian forest, and 2% Swedish, 2% Eastern European?  I mean, WOW.  Impressive.  Doubly impressive because, as we've posted before and many of you know, German and French ancestry is the hardest to call.

23andme still says this woman is German, Italian, British, Northwest European, etc.  In other words, it's pretty far off.  It has a ways to go.

Kudos to Ancestry for getting best-in-class and for cracking the German ancestry code.  We give major kudos to Tim Sullivan and everyone there for their hard work to become the absolute best.

Media Starts to Gets Home DNA Testing for Ancestry Right -- Thank God!

Kristen V. Brown is back with an excellent piece for Bloomberg, on home DNA testing, that is remarkably astute for a piece in the popular media.  

It confirms much of what readers of this blog have seen posted here repeatedly.  It's so good, it's worth quoting at length:

DNA is great at identifying familial relationships like parents, grandparents, aunts, uncles and even second and third cousins. Beyond that, it gets fuzzy.

The genes that make you a superfast runner or that identify you as Irish are less well-studied. The accuracy of any one test depends on the data your DNA is being compared to. One 2009 journal article said consumer DNA tests were akin to horoscopes exploiting the human tendency to hunt for patterns in meaningless data.

So what does it mean when a test says I’m 25 percent Irish?

It’s a misconception that these tests can tell you where your DNA was in the past. 

If a test tells you that you’re 25 percent Irish, what it actually means is that you are genetically similar to other people who are a part of the reference data set of Irish DNA that the company has collected. 

Because each company uses a different algorithm and data set, your results may vary based on which company you use. 

In other words: Take all this with one very large pinch of salt!

Meanwhile, in Slate, appeared another excellent piece by John Edward Terrell.  Here's the quote for you to read for yourself:

Whatever the motivations, the current popularity of commercial genetic profiling worries me for two reasons. One is that these companies may be promising results they can’t actually deliver. 

The notion, for example, that our genes can be used to trace our personal ancestry far back into the past—say, to Genghis Khan, the Emperor Charlemagne, or one of the pharaohs of ancient Egypt—makes little statistical sense. You may disagree, but to me this comes across as selling something more akin to snake oil than science.

What worries me most, however, is that companies offering personal genetic testing customarily seem to report back to those sending along a sample of their spit that they are a mix of different “ethnicities.” This is more than simply statistical nonsense.

We are happy that the mainstream media is finally getting it right, instead of publishing starry eyed pop-sci nonsense about DNA tests.

Don't ever forget: if you come from Central Europe (France, Germany, Italy, or nearby countries), or if you come from a country where there are simply insufficient samples (much of the rest of the world), these DNA tests will wipe your heritage off the map, by telling you that you are something else.  Basically, they're most accurate at the Continental level, unless you happen to come from an island in Europe with massive amounts of people getting tested, i.e., the U.K.

Ancestry DNA Issues Revised Ancestry Estimates, Finds that Germans Exist

Judy G. Russell, the Legal Genealogist, is out with a fantastic new post on AncestryDNA's new ethnicity estimate percentages.

As she wryly notes in the opening, she is delighted to find out that they have discovered that Germans exist.

We've wrote about this before, as have others.  The major testing sites -- some of which are run by people who seem hostile to Germans (America's biggest ethnic group) -- have written Germans off the map.  23andme is particularly bad at identifying German DNA.  They disclose it too, but they bury it in the fine print.

We have been repeatedly depressed by newbies, who know from good paper records that they are a quarter German (or Swiss, or French, or Austrian) say, "duh, gee, duh, this unscientific website tells me I am really 21.2% English wow gee duh am I adopted?"  NO!  The science isn't there yet.  As Judy Russell says, "it's not quite soup."

And it STILL isn't quite soup.  This post focuses on Germans, but the major testing services have an equal problem with Italians, another major American ethnic group.  Poor Italians who get tested often end up with anything but Italian.  (Spare me your pseudoscience on how Italy has been invaded.  EVERY country has been invaded.)  Italy is a long country with many peaks and valleys, and for much of its history was an exporter of population to surrounding areas.  The testing sites need more samples to identify all the different permutations of Italians.

Bottom line, as we've said before, and as every credible scientist says - DO NOT TRUST the ethnicity estimates of the testing services.

DNA Testing for Heritage and Ancestry Is, Simply Put, Inaccurate

You go to take a cholesterol test, and your doctor, very thorough, sends you to four different labs.  One reports your cholesterol is 200, one says it's 180, one says 150, and one says 130...

After a car accident, you get go to four different body shops for quotes.  One says your car's paint color is taupe; one says it's sea blue; one says its ocean blue; and one calls it sea green...

You whip out four different rulers to measure your foot.  One says it's 12 inches; one says its 6; one says 8; and one says 9...

In all of these scenarios, you would make two conclusions:

1.  These test results (or body shops, or labs, or measuring sticks) are not that scientific!

2.  At least three -- and likely all four -- of these results MUST be wrong.

These parables sum up the world of DNA testing for heritage or "admixture."

We've said it before, and we'll say it again.  But today, Kristen V. Brown, a writer for Gizmodo, published an excellent piece discussing the snake oil that Ancestry.com, 23andme, Gencove, FTDNA, and other labs are selling.

Simply put, these labs cannot tell your ancestry.  I repeat, they cannot tell your heritage, or racial or ethnic admixture.  The science just isn't there yet.  And it might never be.

Brown details how she got four different results from four labs.

She also alludes to, but doesn't state um, confidently enough, about the concept about being confident about your known results.

It's what I jokingly (and longwindedly) call the:

"I was born in a tiny isolated village in the Swiss Alps that has never been invaded.  I know my mom and dad, and there's a video of my birth.  I DNA tested them and they are my parents.  I DNA tested my grandparents too, and they are my grandparents.  There were no affairs and no invasions in my town.  I know my great grandparents too and I am their spitting image.  The church records state I am Swiss going back to 1400.  But HELP, this DNA testing service said I'm British.  Am I British?"  (Or Indian or French or Dutch or whatever) problem.

NO, dummy, you're Swiss...

I for one, always read the fine print.  23andme, for example, states clearly that it cannot spot German (or French) heritage 92% of the time!  Germans make up the LARGEST PLURALITY of Americans.  Americans make up the LARGEST MAJORITY of those getting DNA tests done.  Thus, and I only say this half facetiously: these companies are engaging in the virtual ethnic cleansing of ethnic groups, wiping them off the genetic map, with their statements on people's heritage percentages, that are simply inaccurate.  

And 23andme, is, as far as we can tell, the most accurate lab!

Anyway, kudos to Kristen V. Brown and the people she interviewed for explaining it in her Gizmodo piece.  We suggest reading it.

Will Tim Sullivan and Ancestry.com Continue Its VIRTUAL Ethnic Cleansing of Germans?

23andme discloses right off the bat that it cannot identify German or French ancestry 92% of the time.

Ancestry doesn't seem to be able to discern German ancestry too well either, but it doesn't tell its customers that.

Noted: Yet another reader of this blogger just wrote in and shared her experience.  She is 100% German, born in Germany, from a small town, not a big city.  Her ancestors are documented in the region she's from for the last 400 years.  Several of them were well-known and documented.

Ancestry.com called her ancestry as about 50% Scandinavian, 25% Italian, and 25% generic European.  What an epic fail.

How many "white bread" regular Americans, with German ancestry take one of these tests, and misleadingly, their German ancestry is literally wiped away?

We note Germans are America's LARGEST ethnic group, but their ancestry is also often hidden, because German surnames Americanize so well.  For example, Kohl becomes Cole; Schmidt becomes Smith, etc.

As an experiment, with our reader's permission, we ran her raw data through Gedmatch.  Both MDLP (the Magnus Ducatus Lituaniae Project) and Eurogenes were able to call her likeliest ancestry as German.   Dodecad, which specializes in Mediterraneans, was able to call her as German in about half of its tests.

So the question remains:

1.  If the amateurs can call German DNA with reasonable regularity, why the heck can't Ancestry.com?

2.  If Ancestry.com is so bad at identifying America's biggest ethnic group, why doesn't it do the decent thing and tell people?

How DNA Ancestry Testing Works and How Can I Know It's Accurate

When a commercial DNA testing site like Ancestry.com or 23andme or FTDNA tests your DNA, they do not know which snippet came from which of your parents.

For example, if at a given point (a gene, in popular parlance), you have a "C" from your dad and a "T" from you mom (meaning you have brown eyes, but carry the blue-eyes gene), the testing service doesn't know which "letter" came from which parent.

What they then do is try to guess, stringing your DNA out into small chunks or strings of letters.

They then compare these to DNA in their reference database.  23andme's reference database, which is one of the best, if not the best in the world, only has about 11,000 samples in it.  To represent the whole world!


So if you have ancestry from a big country (like France or Germany) or a country that has pockets of deep isolation (like Italy), the odds -- that they have someone from your corner of the country, or your little isolated craggy valley in some mountain chain -- are small.

They then compare the little strings of letters and come up with a likelihood that you have ancestry from one of those reference populations.

23andme has the most scientific test in the business, but it gets French/German/Belgian/Dutch/Swiss/Austrian/Luxembourgisch ancestry wrong 92% of the time.  It most often shows up as "generic Northwest European."  Similarly, 23andme -- the best in the business -- can't identify Italian ancestry 50% of the time.  It often shows up incorrectly as Middle Eastern or Generic Southern European.

The moral of this story is to be patient with the science.  It's not 100% there yet.

If you have documented ancestry from one region, trust your documents.

If you don't have any cousins from a pool you were identified as, then chances are it was a miscall.  (For example, if you have documented Italian ancestry, but it says you are 1/8 Middle Eastern or 1/8 Spanish), then unless you have a known great-grandparent that is 100% such, it's probably a miscall.  (This would mean your parent would test as 1/4, by the way).

Finally, there is a series problem with testing sites, particularly FTDNA's, with the issue of timing.  If you go back far enough, we are ALL Africans, right?  Yet a DNA test telling you that you were African would not be too useful.  Do they mean recently or in the past?

Similarly, as has been well-documented, most European ancestry can be broken down into 3 big chunks: ancient hunter gatherers (Ancient Western Europeans, most similar modern population = Lithuanians); ancient farmers (Ancient Near Easterners, most similar modern populations include Greeks, Sardinians, others); and ancient pastoralists/horse rearers (Ancient Eurasian Steppe Dwellers, most similar modern populations include Ukrainians). But the migrations were really, truly all over the place.

Ancient Near Easterners are NOT modern Near Easterners.  Ancient hunter gatherers in France are NOT the modern French, etc.

If a test tells you that you have some Near Eastern blood, it often is sensing this ancient signal.

It doesn't do you much good for them to say that 6000 years ago, you had some ancestry in the Near East.  Everyone did.

Calculating Matches on Gedmatch: Why CentiMorgans (cM) are more important than SNPs

I have discovered that very very very few people know this, so it is worth posting.

The different testing companies, 23andme, Ancestry, FTDNA, etc. all test slightly different SNPs.  In other words, the "points" on the genome, the "genes" that are tested vary from company to company.

I have seen some people on Gedmatch dismiss a match because "it doesn't have enough SNPs."  Or because "it's not above the SNP threshold."

Gedmatch itself uses a 7 cM and 700 SNPs match to qualify someone as a cousin.

The SNP part is faulty thinking.

Because the testing companies don't test the same SNPs, you can have long stretches that match with a low number of SNPs.

Case in point: Someone who tested on 23andme like I did matched me for 10.0 cM and 1024 SNPs.  That same person on FTNDA matched me for 10.0 cM but just 510 SNPs.  FTDNA tested half of the SNPs that 23andme did (or half of the same set). 

This is key to grasp.  Expect closer matches to you on Gedmatch if your kits start with the same letter (i.e. M for 23andme, F for FTDNA, and A for Ancestry.)  DO NOT DISMISS LOW SNP MATCHES.

What Is the Best and Most Accurate Ancestry Calculator (DNA Testing)?

What Is the Best and Most Accurate Ancestry or Admixture Calculator from DNA Testing?

We Review 23andme, AncestryDNA, Family Tree DNA (FTDNA), DNA.Land, Dodecad, Eurogenes, etc.

Judging from community discussions in online forums, "Admixture" tests, where a company or entity takes your raw DNA data, puts it into a calculator, and then purports to tell you where your ancestors came from -- these are all the rage.  It is not rare for seemingly educated individuals to post on the Internet sheer and utter nonsense about their results, for example, assuming that a calculator identified their ancestry with something close to 100% accuracy.

In the online world, there is no such thing as perfect privacy.  And in DNA, there is no such thing as 100% accuracy for ancestry calculators. 

This is because all people are admixed, but not all ethnic groups form part of the samples.  Put another way, if your ancestors come from a valley in Switzerland where no one has ever been tested, you might show up in a test as French, German, Italian, Austrian, but not Swiss. 

You might say to yourself that you have documented ancestry back to the dawn of time that you are from Switzerland.  You may match other Swiss people exactly.  But because the Swiss are indeed mixes of the groups above, and because there are no specific, micro-targeted Swiss samples in the hypothetical database that match you more closely than those other nationalities, the test would be woefully inaccurate to YOU.  After all, you don't want a test to tell you you might be Northern Italian, if you are Swiss.  (For that matter, do you NEED a test to tell you that?  See below.)

In the online privacy world, they've named protections that are scientifically the best (and do their job pretty darn well) "Pretty Good Privacy."  In the DNA world, all we can hope for is "Pretty Good Accuracy" -- ancestry calculators that are scientifically grounded, don't make claims beyond what they can really do, and ones that get the broad regions correct in the very least.

The coolest benefit about living in a college town (Berkeley for this blogger) is that there are a ton of people from all over the world, with pretty well-defined ancestry.  For example, that Danish exchange student with 500 years of documented ancestors in Denmark?  That's a good candidate for testing some of these calculators.  Enough friends of mine have taken DNA tests, and we've plugged the results in the calculators across several paysites (testing companies) like 23andme and AncestryDNA, and free calculators, like the ones available on Gedmatch.  Who came out on top?

By far, the best and most accurate ancestry calculator is on 23andme.   Like all good scientists, they are humble instead of full of hubris.  They don't profess to give you one set of results and say, "this is it."  Instead, they give you three different results: standard, conservative, and speculative.  Each is pretty darn accurate for most of the people we know who have tested there and other sites.  Bottom line: 23andme's "Ancestry Composition" feature is outstanding, and the best, most accurate one online we could find.

It is our opinion that the least accurate ancestry calculator is at the new site DNA.land.  And the one on FTDNA is a close second.  Both are terrible.  Almost everyone who used the feature on DNA.land reported that the calculator is way off; just not ready for prime time at time of writing this post.

How do these calculators work?  Well, remember, the data that comes out is only as good as the data that comes in.  It is worth to always remember the concept that computer programmers call "GIGO: Garbage In, Garbage Out."  What this means is that if the data on which a conclusion is based is faulty, the answer will also be faulty.  With calculators, this manifests itself two ways: with a shifted focus, or faulty or incomplete baseline data.

By a different focus, we mean: Several calculators, for example, the MDLP Ethnicity Calculator, also offered (with Eurogenes and Dodecad and Gedrosia) at Gedmatch, stands for Magnus Ducatiae Lituania Project.  As you might have guessed from its name, it focuses on the people from lands that used to form the Grand Duchy of Lithuania: places in Northeast Europe, including Poland, Estonia, etc. 

MDLP seeks to be very good at calculating ethnic tidbits of interest to those populations.  But is is good for determining the difference between, say, a Catalonian Spaniard and a Northern Italian?  No, it's actually quite bad on that front.  That's simply not its focus. 

Similarly, there are other calculators on Gedmatch that exist to focus on and cater to Asians, Africans, even mixed race folks.  And within European populations, you have other focuses, like Dodecad, which seems Grecocentric, for lack of a better word.  None of these will do that great outside their focus areas.  So take the results from those ones with a grain of salt, unless you happen to hail from their regions of focus.

Don't believe that?  Think I'm being extreme?  If you are European, try putting your data in a calculator that is focused on another population.  Like the East Asian-focused calculators.  It won't tell you that you are NOT East Asian.  It will tell you which East Asian population you resemble the most.  To be clear: if all a calculator has is East Asian samples, a European will be told he or she is Japanese or Chinese.  This same concept applies within European focused calculators at the regional level.

In terms of bad baselines, recall the Swiss example above.  Europe is filled with micropopulations that exhibit a high degree of population homogeneity (a little inbred, to use the pejorative term).  If a calculator does not have a sample from your micropopulation (the narrow region where your ancestor lived for millennia), then you will get a faulty reading. 

Put simply (to use a French example): It's a big country.  Normans are not Basques, Provencals are not Bretagnes, etc.  That is why the best calculators are HONEST.  23andme discloses quite readily that for the huge populations in the middle of Europe (French, Germans, but also Benelux countries, etc.), it cannot spot the DNA with certainty 92% of the time. 

Does the 23andme website have any drawbacks?  Sure it does.  But they are minor compared to the others. 

First, its "Countries of Ancestry" feature is not what it could be.  But it's important to understand three things:  (1) This is NOT their ancestry calculator, but another feature entirely, so perhaps it's unfair perhaps for us to even review it in this space.  (2) It's experimental, and they state that.  (3) They are wisely phasing it out.  What was the problem with that feature?  Well, it gave you the list of countries of people who have the most matches with you.  Let's say for example you are half Italian, half Polish (a common mix in Chicago).  In other parts of Chicago, another common mix is half Polish, half Irish.  For whatever reason, people of Irish heritage have tested themselves at far greater numbers than the others. Your Polish DNA would overlap (match) with the people who reported they were half Polish, half Irish.  And this feature would then tell you that "a high percentage of the people who have DNA similar to yours are from Ireland."  Do you understand?  It's a huge problem, especially for smaller populations, especially because so many Americans are now half this, half that.  It's just not that edifying then.

23andme also suffers from the same sample issues as many of the other ancestry calculators.  For example, 85% of Italian Americans (TRANSLATION: potential customers, since most people who test are from Britain or the US) hail from just 3 regions in the deep south of Italy: Campania (Naples), Calabria, and Sicily.  Yet the population samples that most of these websites use are from Tuscany.  Even though Dante tried to meld them, Tuscans are not Sicilians and vice-versa. 

Often, these calculators when they see Sicilian or rural Southern Italian genes, they, in effect, say: we don't know what you are! you are kind of Italian but you also resemble, a little bit, people from Cyprus or Jews.  So they give an odd result.  And then you have someone tested who says, "I might be Jewish."  No.  The answer is that your people were not included in the data-set by which the baseline was developed.  If they were, the calculator would recognize you as a run of the mill Sicilian.

All online ancestry alculators also suffer from lack of inter-operability and non-standardized terms.  For example, among the calculators on Gedmatch, some use the term "Caucasian" to mean "generalized European" (which is how it used in common parlance, of course).  Others use it to mean, the specific, like, from Soviet Georgia, Armenia, etc.

Here's the bottom line: don't expect any ethnicity or ethnic-origins calculator to be 100% correct.  Don't expect new insights if you have confirmed records.  In other words, if you look just like your dad (you're not a bastard), and you're not adopted, and you have records going back centuries -- why do you need an ethnicity calculator to begin with?

These admixture tests can help if you were adopted, and want to have a sense of where to start.  But keep in mind, the largest plurality of Americans come from German heritage, and yet the best currently cannot identify German DNA 92% of the time.

Avoid the mythology and those who oversimplify.  There are reliable sources out there in genetic genealogy, like Debbie Kennett -- and there are a lot of charlatans.  Be careful whenever someone oversimplifies to the point of exaggeration, falls into stereotypes, or tells you what you want to hear.  With DNA as with everything, the most parsimonious answer is often the best.  The exotic is often wrong.

As the science improves, you can't go wrong using the Standard or Conservative setting on the 23andme Ancestry Composition test.

READ MORE:

DNA Testing Is Often Inaccurate

Summary of Recent Pieces on the Topic

The Percentages Are Off

 

The Top Ten Myths of Genetic Genealogy, Archaeogenetics, and DNA Testing (10 through 7)

Any scientist visiting the websites or online forums of Eupedia, Anthrogenica, or Apricity (to name a few) is mortified.  The amount of shorthand claims, pseudo-science, pop-anthropology, and myths perpetuated there are truly astonishing, and quite sad.  Below we list the Top Ten myths of this world.  We will update the post over time to link to specific offenders, so you can share the laughs we shared.

Don't be an idiot.  Learn these myths, and for the love of all things holy, don't propagate them!

10.  If you are of Scandinavian heritage (Denmark, Norway, Sweden), you are a "Viking."  

Example post: "my gma is half Swedish and I am very adventurous; must be the Viking LOL."  

Vikings were the marauders sailing from Scandinavia who invaded many parts of Europe during the years of approximately 600 AD - 1200 AD.   Those of Scandinavian blood are emphatically NOT "Viking."  The Vikings were the adventurous ones who left.  Scandinavians are descended of the ones who stayed home.  

While Scandinavians may share common origin with the Vikings dating back 1500 years, technically it's not correct to say they are descended from them.  And to the extent there is a gene for adventure-seeking, violence, or the so-called, "warrior" gene, it's more probable that the ones who stayed in Scandinavia (as fishermen and barley farmers) do NOT have that gene.

Many Russians, Ukrainians, English, Scots, Calabrians, Sicilians, and Northern French have a better claim to be "directly descended from Vikings."  Sorry.



9.  You can determine by a test on Eurogenes or Gedmatch the precise percentages of EEF-ANE-WHG that you are.

For the uninitiated, these acronyms stand for "Early European Farmer," "Ancient North Eurasian," and "Western [European] Hunter Gatherer."

Example post: "Username: SteppeOverlord  EEF: 21.345%, ANE: 19.876% WHG 58.779."

It's important to note that these hypothetical populations were reconstructed from...ONE SAMPLE EACH.  Thus, when you take the Eurogenes EEF ANE WHG test, you are comparing yourself to each of three skeletons: the EEF is the LBK sample found in Stuttgart, Germany.  The ANE is the Mal'ta boy found in Siberia.  The WHG is the Loschbour skeleton found in Belgium.  Citation.

These populations were themselves admixed, especially the Stuttgart sample.  It's not accurate to use one exemplar to represent an entire group, especially ones with the huge geographical ranges of the acronym populations.  It's much more accurate to say that you tested whatever percentage in common with Loschbour, Mal'ta, or Stuttgart.  

 Many of the genes inherited so many generations ago will be the result of identical by state, (more or less coincidence, or breeding back, in a way), than Identical By Descent.  Citation.  Europeans are a homogenous lot, and these tests don't therefore reveal much, if anything, and the terminology, turned to shorthand, stinks.


8.  Admixture percentages are due to a historical event.

Example post: "OMG!  I am English, Irish, German, and Polish.  But Dodecad says I have 6% Siberian; this must prove the legend in my family that my great-grandmother was a Cherokee princess!"

Or:

"I am South Italian.  But Eurogenes says I have 12% southwest Asian.  Must be the Greek blood!"

People tend to overestimate historical events (i.e., those we know about due to past events being recorded in writing), but tend to underestimate non-historical events.  This is a recent-ness bias that comes from a little knowledge about history, often expressed in shorthand, (i.e., South Italy was Greek).

It is however, almost always not true.  In the first example above: many Europeans, especially Northern Europeans, test positive for some Siberian/ANE/even Native-American-like ancestry, but this is almost certainly the result of ancient Admixture from the first Indo-Europeans from the steppe, who had substantial Asian-like ancestry.  For the second example: the people who populated Italy in prehistoric times were descended in many cases from the first farmers, who came from the southeast fringes of Europe.  Such signals in modern ancestry are way more likely to indicate ancient admixture from population sources with common ancestry to historical populations.

Sorry, but the boring is almost always more true than the interesting.



7.  People from places with many years of recorded history are more admixed than people with less history.

example post: "If you are of South Italian ancestry, you're probably part Roman, Greek, Scandinavian, Arab, and Jewish."

This one is so obvious it is painful to have to post.  But it's the corollary of number 8 above: a little historical knowledge being dangerous.

Imagine two regions: Region 1 is fairly remote, but has had extensive writing for 2600 years, and every marauder, political shift, kingdom, invasion, battle, language spoken, and petty dukedom is recorded in glorious detail.  Imagine another region, Region 2, that has had extensive writing and civilization for only about 1100 years.  There are large gaps in knowledge of what happened there, because of the lack of historians.

I just described Basilicata, Italy and Hesse, Germany.  Yet so many online "mytholographers" perpetuate the notions that people like Italians, Jews, and Greeks (i.e., those with 25+ centuries of intense recorded history) are more admixed than those without such extensive documentation (i.e., Germans, French, etc.)

You can't escape this, on any online forum, people speculating on exotic sources in Italian ancestry, and almost no one does this for Germans and French.

Just because we don't know who was invading another area during prehistory or the Dark Ages, does it mean it didn't happen?  Just because we don't know the name of the king who pillaged a territory, does it make him any less historical?  Because there is no Trojan War story for Hesse, Germany, does it mean there was no warfare, invasion, or exotic influences?

The French and Germans are so "admixed" (i.e., generic European) that 23andme cannot identify their DNA 92% of the time.  Citation.  Yet the poor Greeks have to tolerate in every discussion, excruciating detail and speculation about every single exotic strain in their blood.

Aside from the remotest, hard-to-get-to, isolated regions of Europe (Finns, Northwest Irish, Basques, and Sardinians), everyone has been invaded, repeatedly, and everyone is very very admixed.  The paradigm, of focusing only on certain peoples for this, has to change, because it's simply not accurate.

Check back soon for the rest of the Top 10 list.