DNA Testing – Risks and Limitations

Accessible and affordable Genetic DNA testing has been around for many years and can produce positive and exciting outcomes for your family tree research. However, while the major providers are great at promoting the benefits of doing a test, they are not as great at ensuring testers are aware of some of the risk and limitations, especially before submitting their DNA sample.

Some of the Risks of DNA Testing:

• Unexpected results – there is the potential that the results may uncover different parentage than expected, or additional relationships (e.g. an unknown half sibling) either for yourself or a relation (e.g. for your parent or grandparents).
• Limited results – there is the potential that you will only get limited results that help with their family history research (and potentially no results for Y-DNA or mtDNA). Their number of matches will increase as more people take tests.
  • An autosomal DNA test (atDNA) can only reveal shared ancestry within the last five to seven generations. Beyond that, it is not possible to reliably predict relationships using atDNA, which is the common commercially offered test (Ancestry, MyHeritage, etc.)
• Other uses of test results:
  • Most of the companies provide the ability to participate in anonymised research, and most also offer medical/health profiling as an additional service (this is unlikely to aid genealogical research).
  • There have been several high-profile cases of DNA databases being used to aid police investigations. The key providers that continue to be used for police investigations are FamilyTreeDNA, MyHeritageDNA, and GEDmatch. All have Terms and Conditions which make it clear what is and is not allowed so you are fully consenting to how your information is used.
• Interpretation & Understanding Results – If you do not have the personal experience or knowledge to fully understand your results, it is strongly recommend you consult a professional for advice and guidance. If you are in this situation, either pre-or-post testing, I’m happy to have a conversation.
• Unrealistic Expectations – as I explain below, DNA Testing is not a short cut to researching your family tree. There are questions it can answer, but there are many that it cannot, at least not on its own. It’s important to know if DNA testing is the right approach, and if so, which type of DNA Test might provide the results you’re looking for.

Limitations of DNA Testing:

• DNA testing is not a short cut to researching your family tree. You will still need to undertake traditional research using documentary records otherwise you will likely not be able to understand how you are connected to your matches.
• Just because a DNA match has a family tree linked to their test kit, it does not mean that it’s accurate.
• As our DNA is inherited from a subset of our genealogical ancestors, there are some genealogical relatives that you will not share DNA with, but you are still related.
• While siblings have the same genealogical tree, they do not have the same genetic tree as each other – unless they are identical twins.
• If our recent ancestors had small families with few children, who themselves had few children, our DNA matching list with close cousins may be quite limited.

Adoption Research

• If you are an adoptee (or an adoptee’s relative) searching for birth family, there are additional limitations for communicating with any birth family to comply with the laws in your country.
• It is recommended that you have an accredited intermediary in place who can support any communications once birth family has been identified. This could be through a lawyer, social worker, or adoption support agency.
• Be mindful that while some may welcome hearing from a child they gave up for adoption, others may not – it often depends on the circumstances of the adoption.

My own experience with DNA

I originally did my first atDNA test through Ancestry roughly 12 years ago. I have since uploaded that raw data file to several other providers in order to compare results and discover additional relatives in their individual databases.

My experience has so far been positive. I have connected with and met new cousins I previously didn’t know about. This in turn led to photos and stories about my grandparents before they came to Canada, and the family they left behind in England. I’ve uncovered new surnames and branches of the tree that were previously unknown, and there have been no surprises or ‘skeletons’ hidden in the closet. (yet)

I hope your experience is as positive!