13 April 2013

Using Common Sense to Make Sense About Genealogical Uses of DNA Tests

The immediate world-wide sharing of information in our modern age is both a blessing and a curse. We know what is happening this very second in a place thousands of miles away. Disagreements between factions can generate so much data it is difficult to keep up and get to the truth. Misunderstandings occur when minor differences in usage of terms cause a reader to think of one thing when the writer meant something else.

A consumer should always do their homework before parting with precious dollars. This applies whether you are buying a house, where you'd have an experienced person inspect the plumbing and foundations, or a vacuum cleaner where you might check out reviews in Consumer Reports.1 It is the responsibility of a consumer to understand what they are buying. It is common sense to investigate before you buy.

It is the job of a marketing person to present his company's product in the most favorable way. It is the job of a saleswoman to convince you to buy the product from her company. It is the job of entertainment media companies to gather as many viewers or readers as possible with a good story. These may not always be the best people from whom to seek impartial advice and accurate information.

While there are some unscrupulous companies out there taking advantage of consumers (aren't there always?), there are also companies trying to do the right thing. Good companies are trying to provide a balance between tests reflecting the science we have tested and trust and the leading edge tests demanded by those who must gather more evidence to prove or disprove their theories.

When the consumer is not knowledgeable about a product, as is often the case with genetic genealogy tests, she needs impartial advice so she won't be unhappy with the end result. A DNA test is not a magic bullet to solve your genealogical problems. It is one more piece of evidence to weigh along with all the other evidence you have gathered before you reach a conclusion. Exactly what you are trying to prove has a huge impact on determining which DNA test, if any, is appropriate for your goals.

One problem in our modern world is that there are many groups out there now with names that make them sound knowledgeable and impartial, but every group is made up of humans who may have a secret purpose we don't know about. With marketing materials, the purpose is not a secret. We know the purpose is to sell us something. So we need to read the statements even more carefully. We need to talk to someone who knows the product so we can understand what we are getting.

Specialists, including scientists, use terms differently than the man-on-the-street does. Specific phrases have very specific meaning to scientists that may not be clear to those who are not specialists in the same field. If we don't understand what the term means to the scientist we may misunderstand the point being made.

I received a copy of a flyer (which I am deliberately not supplying a link to) written by the Sense About Science group in the UK. This is now being used by some in the U.S. to support a statement that genealogical testing is not useful for genealogy. The Sense About Science flyer seems to be related to a dispute between two academic groups in the UK.

A careful reading of the flyer shows most of the negative comments are directed at using DNA analysis to determine ancient origins. The science and the available databases are not at a point where we can accurately predict ancient origins. No matter what you've seen on TV we can't be 100% sure someone is descended from the Queen of Sheba, Zulus, Vikings, or any other ancient population. This is exactly the reason that organizations like National Geographic have the Geno 2.0 project2 — we need to learn more. To learn more we need more people to test and more analysis of the results.

CeCe Moore covers this well and illustrates the differences in results displayed by three of the big DNA testing companies in the U.S.3

One small inset in the Sense About Science flyer clearly indicates "There are some things genetic ancestry tests can tell you quite accurately" and has two good points. The first is that one of those credible uses of genetic ancestry tests is "to supplement independent, historical studies of genealogy." That is EXACTLY what our genealogical research is - an independent, historical study of our personal genealogy. The genealogist is the independent researcher. The second point is that, "To answer a specific question about individual ancestry with any degree of confidence requires a combination of historical records and genetic information." And that is exactly what the Genealogical Proof Standard4 teaches us. We make no conclusions based on a single piece of evidence. We gather all of the relevant evidence from a reasonably exhaustive search, including the DNA test results, then analyze and correlate it to form a logical conclusion.

The magic solution to all of your genealogical problems will not be printed in so many words as part of your test results. But DNA tests have many uses in genealogical research. Many researchers have made wonderful discoveries about their family history because of what they have learned from a DNA test.

Getting the most information from DNA results to further your genealogical goals requires understanding what tests are available, what results can realistically be expected, what your goal is and which of the tests can help achieve your goal, who is alive in the line of interest who can provide a DNA sample, and, most importantly, how to analyze and interpret the results when you get them, correlating the DNA results with all of your evidence from traditional research. It requires some work on your part, a lot of work, but in some situations DNA test results can provide the key to solving a genealogical problem even if you won't learn whether your ancestor was a Zulu or Viking warrior or the Queen of Sheba.




1. Consumer Reports (http://www.consumerreports.org/ : accessed 13 April 2013).

2. "GENO 2.0: THE GREATEST JOURNEY EVER TOLD. Your Story. Our Story. The Human Story.," The Genographic Project, National Geographic (https://genographic.nationalgeographic.com/ : accessed 13 April 2013).

3. CeCe Moore, "Comparing Admixture Test Results Across Companies (otherwise known as "ethnic" breakdowns): FTDNA, AncestryDNA, 23andMe and Geno 2.0 - My Review," Your Genetic Genealogist blog, posted 18 December 2012 (http://www.yourgeneticgenealogist.com/2012/12/comparing-admixture-test-results-across.html : accessed 13 April 2013).

4. Christine Rose, Genealogical Proof Standard: Building a Solid Case, 3d ed. (San Jose, California: CR Publications, 2009).


For more information on the academic dispute and the response of a UK genetic genealogist see:

Debbie Kennett, "Sense About Genealogical DNA Testing," Sense About Science blog, posted 15 March 2013 (http://www.senseaboutscience.org/blog.php/41/sense-about-genealogical-dna-testing : accessed 13 April 2013).

Debbie Kennett, "Sense About Genealogical DNA Testing," Cruwys news blog, posted 15 March 2013 (http://cruwys.blogspot.com/2013/03/sense-about-genealogical-dna-testing.html : accessed 13 April 2013).

Debbie Kennett, "Sense About Genetic Ancestry Testing," Cruwys news blog, posted 8 March 2013 (http://cruwys.blogspot.co.uk/2013/03/sense-about-genetic-ancestry-testing.html : accessed 13 April 2013).

Jonathan Bucks, "Rector assessed: Moffat blasted over 'laughable' scientific claims," The Saint, "an independent newspaper written and run by students at the University of St Andrews, Scotland," posted 7 March 2013 (http://www.thesaint-online.com/2013/03/rector-assessed-moffat-blasted-over-laughable-scientific-claims/ : accessed 13 April 2013).


To cite this blog post:
Debbie Parker Wayne, "Using Common Sense to Make Sense About Genealogical Uses of DNA Tests," Deb's Delvings Blog, posted 13 April 2013 (http://debsdelvings.blogspot.com/ : accessed [date]).

© 2013, Debbie Parker Wayne, CG, CGL, All Rights Reserved

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