DNA

About that DNA Test You Got for the Holidays… Part 2: Privacy

silence means securityThe first post from this series examined the most common DNA test used for genealogy, the autosomal DNA test (atDNA), and discussed what the test can, and cannot do, along with a few words of caution about expectations.

This post continues the theme of questions a genealogist might ask a client regarding their desire to take a DNA test. Remember, genealogists want you to test. Genealogists also want informed consumers and educated clients. My typical first question – why do you want to test? or another way of looking at it, what are your goals for testing? – appeared in Part 1.

Second question: what are your privacy concerns?

We need to have a discussion about privacy. All genealogy research is deeply personal, and nothing more so than your genetic material. My aim is not to scare you. I want you to take a DNA test. I want you to be comfortable, and understand what it is, what it does, and what the future holds.

If you are considering DNA testing or even if you have already tested, please read the testing company’s Terms and Conditions. Carefully. Read the Informed Consent. Carefully. Read the Privacy Statement. Yes, carefully. It’s a lot of legalese, and it isn’t easy to digest, but please do it. Some companies value your privacy, some value your genetic data. Some will use it for their greater gains.[1]

Every testing company has slightly different Terms and Conditions, Informed Consent, and Privacy policies. The International Society of Genetic Genealogy Wiki maintains comparison chart[2] which can help answer some of these questions, but nothing, nothing, replaces reading the documentation. I know this feels like a homework assignment, but it’s one of those tasks that makes you a better student in the end.

As you read, take note of the following: where is your test processed? Who owns the genetic data – you or the company? What are the opt-in or opt-out options? Will your DNA be assessed for health or other traits? Is the testing company in contractual partnership with any other companies? Who owns the DNA testing company?

Another essential set of questions to ask yourself regarding DNA testing: have you prepared yourself for the possibility of unexpected results? Have you considered how you will approach family members, or strangers, when communicating about results, expected or not? Do you know if any other family members – siblings, parents, cousins – have tested?

Now that the legalese is out of the way, I want to address a few myths:

  • When I test, my DNA will be online for anyone to see. Your DNA test is only viewable at the company with which you choose to test. Depending on the company, it’s up to you to control and share the information with potential matches, only within the company. If you want to share more widely there are options that you control.[3]
  • If I test, law enforcement will be able to take my DNA. False, sometimes true, or, it depends. Here is what it depends upon: if you test and keep the results within the database of the testing company, law enforcement would be required to obtain a court order to access your DNA.[4] Using a company’s website is not what happened with the now-famous case of the Golden State Killer. A third-party testing site called GEDmatch was used. On GEDmatch, users take their raw DNA results and upload them to GEDmatch, and the results are compared to users who have done the same process. GEDmatch does not test DNA, it provides a public platform upon which people can openly share and look for matches across the different testing sites.
  • My sibling tested so I don’t need to – my DNA is already “out there.” Not really.[5] Some of your DNA might be “out there,” as full siblings have about 50% of their DNA in common. Even identical twins do not have 100 percent identical DNA.[6] Additionally, testing siblings, parents, cousins, etc. can be an important part of a DNA research plan. Before that can happen, have a conversation with your sibling (parent, cousin, etc.) about DNA testing and see if you can agree on privacy settings, where to test, who to test, expectations, and more.

Conclusions

Finally, the information in this post is based on my experience testing myself, family members and clients, as well as my study of DNA testing for genealogy. I do not receive advertising or other revenue from any of the DNA testing companies. I am not a lawyer and please do not consider this legal advice.

[1] “Opting out,” The Legal Genealogist, https://www.legalgenealogist.com/2015/07/26/opting-out/, accessed 2 Jan 2019.

[2] “Autosomal DNA testing comparison chart” Tim Janzen for ISOGG Wiki, https://isogg.org/wiki/Autosomal_DNA_testing_comparison_chart, accessed 2 Jan 2019

[3] Based on the information provided by testing companies and reported on at “Autosomal DNA testing comparison chart” Tim Janzen for ISOGG Wiki, https://isogg.org/wiki/Autosomal_DNA_testing_comparison_chart, as reviewed on 2 Jan 2019. Policies can change. This statement assumes appropriate security measures are in place to prevent data hacks.

[4] If you search the name of a DNA testing company plus the phrase “law enforcement,” for example, “FamilyTreeDNA+law enforcement,” you will be able to read each company’s policy on granting access.

[5] Time to brush up on recombination, which is the exchange of DNA segments between the two copies of a chromosome (maternally inherited and paternally inherited). The creation of each egg and sperm is an independent event, and the newly formed chromosome in the fertilized egg is a patchwork of contributions. Siblings inherit different portions. Basically, that’s why they are siblings and not clones! I know, I snuck in more science.

[6] “Identical Twins’ Genes are Not Identical.” Anne Casselman, Scientific American. https://www.scientificamerican.com/article/identical-twins-genes-are-not-identical/, accessed 8 Jan 2019.

Image: “Silence Means Security.” Record Group 44: Records of the Office of Government Reports, 1932 – 1947. Office for Emergency Management. Office of War Information. Domestic Operations Branch. Bureau of Special Services. 3/9/1943-9/15/1945 Series: World War II Posters, 1942 – 1945, War and Conflict Number 828.

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About that DNA Test You Got for the Holidays… Part 1

Everyone’s doing it, which sounds like a comment made at a high school party. But according to recent reports, more than 14 million DNA testing kits have been sold – by one company alone! It’s anyone’s guess how many total kits have been actually processed (vs. sold), but the number could easily reach 20 million in 2019.[1] This post will tackle the most popular type of test, autosomal DNA (atDNA). Future posts will address privacy and the two other types of DNA tests taken for genealogical research: mitochondrial, also known as mtDNA, and Y-DNA.

23 chromo

There are loads of articles and Internet searches for “Best DNA Test kit,” but I have yet to find an article in a major media outlet that was written by a genealogist. If you ask a genealogist which testing company is best, I would hope they would turn around and ask you a question or two back, because like all things genealogy, DNA testing is personal, and there is a lot to consider.

If you were to ask me, my first question would be: Why do you want to take the test?

Possible answers:

  • I want to know my ethnicity
  • I want to get my family tree

Let’s pause here. These are the two most common responses I hear, and the ones I spend the most time discussing. DNA testing doesn’t really do either of these things well, even though the commercials promise otherwise.

Here’s the deal. Autosomal DNA tests (atDNA), the most common tests on the market, run from $50-80 or so, depending on the company and the sales. Companies promise your ethnicity estimate(s), and some say that can get to a very granular level with the tests. How do they do that? Beware: science content ahead – or more accurately – beware: statistics ahead!

An atDNA test uses data from the sequence of information on a person’s 22 autosomal chromosomes.[2] The testing company compares individual’s atDNA results to reference samples, looking for identical or similar strands of DNA on the different chromosomes, known as markers.

The data for the reference samples comes from individuals tested with known ancestry from a specific region, going back many generations. These samples help to establish unique genetic signatures from divergent regions around the globe. DNA testing companies take these reference samples and create proprietary databases, which form the basis of the ethnicity estimates.

Scientists still face challenges in this emerging field of study. The analysis is limited by the reference populations used. To date, only a few ancient human remains have yielded usable atDNA,[3] so the reference populations rely on living samples. Results can change as more data and refinement of reference populations change. Each company has a proprietary database, so one person testing with different companies will quite possibly receive different results.

The results are limited by the reference samples (populations) used in the analysis, therefore it is important to remember that the test provides only an ethnicity estimate, and sometimes the tests do not reflect the historic paper trail.

The discussion might continue with some follow up questions: But the results say I’m [Spanish, French, Scandinavian, etc.] but none of my ancestors are [Spanish, French, Scandinavian, etc.]. Is my grandfather not really my grandfather? Where is my German? Is the research you did for me wrong?

No, the historic research isn’t wrong, and though non-paternity events do happen, remember these are ethnicity estimates. The ethnicity of people from Europe is particularly challenging to pinpoint,[4] as brilliantly explained in the maps at this blog entry at DNAeXplained.[5] Think of it this way: could you really tell the difference between someone from Illinois vs Missouri vs Wisconsin? Or Connecticut vs. Massachusetts vs Vermont? How can we expect DNA to know the difference between France and Germany when the borders of those countries changed many times in the last 300 years?

Remember, ethnicity estimates are predictions limited by the reference samples (populations) used in the analysis, and because of the limitations of the reference samples, sometimes the estimates do not reflect the historic paper trail.

Given the political climate of the past few years, I have to raise another, more ominous reason I’m not so keen on the ethnicity estimates: nationalism.

For a lot of places in Europe, the country some DNA kits assign to the results might not have been a country when your ancestors lived there. Germany, not a country until 1871. Italy? Same. Poland, and many other places in Eastern Europe, didn’t exist or had ping pong borders until after WWII, and for some, not until the break-up of the Soviet Union. Current country borders in Africa and South America do not resemble their pre-colonial kingdoms and tribal regions.

Why do we want to plant a flag on our DNA? Sure, it’s cool to know where you are from simply by spitting or swabbing, but the negative undercurrent of relying on ethnicity estimates to “prove” whiteness or align with a certain country or nationality or race needs a careful eye.[6]

Now, about that family tree. Many people assume that when they receive the results of their DNA test, the website will display an amazing family tree. This might happen if you test and match with a relative who has done extensive work, but most of the time, there will be no tree.

Why do genealogists want their clients to test? It’s for the matches. The matches are the prize. Matches allow genealogists to break down brick walls, determine unknown maiden names, locate lost family, rebuild broken branches of trees, and more. Matches are essential tools, particularly if an adoptee is seeking information on a biological family.

How do matches work? Aren’t they just estimates, too? In a word, no. Matches are hard science, comparing your DNA with others who have also tested with the same company. If you match with another person who tested at the same company, it means that both of you have an ancestor in common.

Two main factors influence the significance of a match between people: the number of segments of matching DNA; and the length of the matching segments. The longer and more prevalent the strands, the closer the match. Using these matches, genealogists can start to piece together unknown branches of a tree. This work can be challenging, take patience, and time.

Another essential question to ask yourself regarding DNA testing: have you prepared yourself for the possibility of unexpected results? Have you considered how you will approach family members, or strangers, when communicating about results, expected or not?

Don’t be afraid to jump into DNA testing for genealogy. Just be sure to do it with your eyes, and not just your mouth, wide open.

Conclusions

Finally, the information in this post is based on my experience testing myself, family members and clients, as well as my study of DNA testing for genealogy. I do not receive advertising or other revenue from any of the DNA testing companies. I am not a lawyer and please do not consider this legal advice.

[1] “Autosomal Testing Growth,” The DNA Geek, https://thednageek.com/dna-tests/, accessed 30 Dec 2018

[2] “Autosomal DNA,” International Society of Genetic Genealogy, https://isogg.org/wiki/Autosomal_DNA, accessed 23 Dec 2018

[3] “Ancient DNA,” FamilyTreeDNA research group, https://www.familytreedna.com/groups/ancient-dna/about/background, accessed 2 January 2019

[4] There are some exceptions, notably the autosomal DNA of people with Ashkenazi ancestry.

[5] “Ethnicity is Just an Estimate – Yes, Really!,” DNAeXplained – Genetic Genealogy, https://dna-explained.com/2018/12/28/ethnicity-is-just-an-estimate-yes-really/, accessed 30 Dec 2018

[6] “Written in Blood,” Joan Donavan, Anthropology News. http://www.anthropology-news.org/index.php/2018/07/12/written-in-blood/, accessed 20 Dec 2018

Image: Bolzer et al., (2005) Three-Dimensional Maps of All Chromosomes in Human Male Fibroblast Nuclei and Prometaphase Rosettes. PLoS Biol 3(5): e157 DOI: 10.1371/journal.pbio.0030157 Image 7a, https://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.0030157, used under Creative Commons Attribution 2.5 Generic license, accessed 3 Jan 2019