Showing posts with label home DNA tests. Show all posts
Showing posts with label home DNA tests. 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.

Wednesday, August 22, 2018

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.