Musings on DNA Genetic Genealogy

Last updated and URLs checked: 21 September 2020. I remain quite skeptical though I know plenty of people who love using DNA testing to identify cousins. - gmc

At the Family History Workshop last month, several participants were thrilled to have conducted DNA profiling of themselves and other family members. I, however, remain very skeptical since anything as heavily marketed as ancestry DNA testing cannot truly be all that it claims to be. My go-to guy family historian, Michael John Neill, has his doubts as well which he mentions in a Genealogy Tip of the Day blog post "DNA Will Not Solve Every Problem" and "Not Everyone Gets the Same DNA."  He sees genetic DNA ancestry testing as a tool that needs to be backed up with historical evidence specific to your lineage.

http://www.yourgeneticgenealogist.com/2012/12/comparing-admixture-test-results-across.html

I decided to do a bit of research about genetic ancestry testing and the industry that has sprung up around it. With key player  Ancestry.com projected to do $850M in business during 2017, companies have a vested interest in getting the public to sign on and spit whether or not one can find out anything useful about their specific ancestors by doing so.

First I read "What is Genetic Ancestry Testing?" from the US National Library of Medicine. The NIH breaks down genetic ancestry testing into three types:

• Y Chromosome testing - only males have a y chromosome
• Mitochondrial DNA testing
• Single nucleotide polymorphism testing - which is the type that the Ancestry.com advertisements tout since it deals with large numbers of variations (single nucleotide polymorphisms or SNPs) across a person’s entire genome that are then turned into percentages of European, African, Asian, Native American ethnicities.

 https://tracingafricanroots.wordpress.com/ancestrydna/african-american-results/

The International Society of Genetic Genealogy (ISOGG) promotes the use of DNA testing in genealogy. Its Wiki has more than 500 articles on the topic. Family Search Magazine named it one of 2017's best genealogical websites.

Detailed information about genetic ancestry testing is available from Sense About Science. This United Kingdom based independent campaigning charity challenges the misrepresentation of science and evidence in public life.  They state that they advocate openness and honesty about research findings, and work to ensure the public interest in sound science and evidence. Their guide explains why DNA tests are used in population research and why said tests do not provide accurate information about an individual’s ancestry, to wit:

• Our individual ancestry is much shallower than people might imagine – the best estimate is that the most recent person from whom everyone alive today is descended lived just 3,500 years ago.
• As we look back through time we quickly accumulate more ancestors than we have sections of DNA, which means we have ancestors from whom we have inherited no DNA.
• There are millions of possible ‘stories’ of your ancestry. To know whether any one of them is likely to be true, it would need to be tested statistically for its likelihood against other possibilities.
• The genetic ancestry business uses a phenomenon well-known in other areas such as horoscopes, where general information is interpreted as being more personal than it really is (the so-called Barnum effect).

The Smithsonian National Museum of Natural History's exhibit 'Genome: Unlocking Life's Code' discusses genetic ancestry testing. The exhibit also discusses the African Diaspora and its influence on heredity and genealogy.  You can view a video made at the Museum entitled "The African Diaspora: Integrating Culture, Genomics and History" Symposium in 2013.

DNA eXplained: Genetic Genealogy has a page called Concepts - Calculating Ethnicity that explains the complexity of how one inherits DNA from parents, grandparents, great grandparents, etc. For example, I have one sister and though we physically favor each other and all parents and grandparents, great grandparents, etc. are (presumed) to be the same people, our DNA is different. In fact, DNA is inherited in chunks, and often you receive all of a chunk of DNA from that parent, or none of it. Seldom do you receive exactly half of a chunk or ancestral segment. In other words, even full siblings of the same gender do not necessarily have the same ancestral chunks as it were.

I searched on the term "Genetic Genealogy" in the Academic Search Premier database inside DISCUS and got 181 hits for the years 2001 - August 2020, some of which are too scientific for my liberal arts educated mind and some of which open with fascinating sentences as "Virtually every person living in Europe today shares a common set of ancestors that lived about 1,000 years ago" or have a provocative title such as "The Woman Who Solved 109 Criminal Cases." [Please note: Only people with valid library cards for Libraries that subscribe to the DISCUS service can access the Academic Search Premier database.]

You can even find testimonials about which of the 30 or so companies in the business of testing DNA for genealogical purposes online. "Best DNA test" by Lydia Ramsey appeared on the Business Insider website in April 2017. ISOGG lists companies performing the tests on their WIKI. You can also see what others describe as the Best DNA tests for specific purposes at SmarterHobby.com and  Family History Daily among others.

For me, though, I agree with Real Clear Science that "Genetic Ancestry is Basically a Horoscope" and given my thriftiness, I could not be bothered to spend my hard-earned income in this way. (Though I do admit that I read my horoscope most every day just for fun.) However, if you want to drop some bills and get your genetic genealogy done, have fun! You can compare your results with others at our next genealogy program.