Showing posts with label ethnicity calculators. Show all posts
Showing posts with label ethnicity calculators. Show all posts

Friday, February 12, 2021

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.

Saturday, January 30, 2016

In Praise of Roberta Estes and DNAeXplained.com

In a world of pseudo-science and echo chambers, a few blogs stick out for being mostly in touch with reality.  In the world of Ancient DNA, Dienekes, although less active than before, has pioneered much in the field of DNA, and still has many serious scientists who comment there.

In the world of DNA for Genealogy, one blog sticks out.  It is Roberta Estes' DNAeXplained.com.  Of all the blogs and websites dedicated to disseminating information about DNA, hers is consistently factual, science-based, and yet easy to understand. 

This scientist came across a few of her posts, and I daresay they are mandatory reading for anyone seeking a better understanding of their DNA.  Below are links and highlights:


Step 1:  Creation of the underlying population data base.
Don’t we wish this was as simple as it sounds.  It isn’t.  In fact, this step is the underpinnings of the accuracy of the ethnicity predictions.  The old GIGO (garbage in, garbage out) concept applies here. . . .

The third way to obtain this type of information is by inference.  Both Ancestry.com and 23andMe do some of this.  Ancestry released its V2 ethnicity updates this week, and as a part of that update, they included a white paper available to DNA participants.  In that paper, Ancestry discusses their process for utilizing contributed pedigree charts and states that, aside from immigrant locations, such as the United States and Canada, a common location for 4 grandparents is sufficient information to include that individuals DNA as “native” to that location.  Ancestry used 3000 samples in their new ethnicity predictions to cover 26 geographic locations.  That’s only 115 samples, on average, per location to represent all of that population.  That’s pretty slim pickins.  Their most highly represented area is Eastern Europe with 432 samples and the least represented is Mali with 16.  The regions they cover are shown below. . .

No matter which calculations you use relative to acceptable Margin of Error and Confidence Level, Ancestry’s sample size is extremely light. . . .
 


"having Haplogroup Origins and Ancestral Origins indicating Native American ancestry does not necessarily mean you are Native American or have Native American heritage. This is a very pervasive myth that needs to be dispelled. . . .

The good news is that more and more people are DNA testing.  The bad news is that errors in the system are tending to become more problematic, or said another way, GIGO – Garbage in, Garbage Out.

....

There are a very limited number of major haplogroups that include Native American results.  For mitochondrial DNA, they are A, B, C, D, X and possibly M.  I maintain a research list of the subgroups which are Native.  Each of these base haplogroups also have subgroups which are European and/or Asian.  The same holds true for Native American Y haplogroups Q and C.
In the Haplogroup Origins and Ancestral Origins, there are many examples where Non-Native haplogroups are assigned as Native American, such as haplogroup H1a below.  Haplogroup H is European...

One of the problems we have today is that because there are so many people who carry the oral history of grandmother being “Cherokee,” it has become common to “self-assign” oneself as Native.  That’s all fine and good, until one begins to “self-assign” those haplogroups as Native as well – by virtue of that “Native” assignment in the Family Tree DNA data base.  That’s a horse of a different color.