Unexpected DNA Results

Ann Cannon is an advice columnist at the Salt Lake Tribune, but her advice here is another worrying indication that there needs to be a great deal more education regarding how to interpret the results of DNA testing.

Ask Ann Cannon: A DNA test raises questions about my mom’s dad. Now what?

“Dear Ann Cannon 
“We gave our elderly mother a DNA test just for fun. She now knows her father was NOT her father. And no one is alive to answer her questions. She’s a mess right now. How reliable are these tests anyway? Our impulse as siblings is to tell her they’re not reliable and to forget the results. What do you think?
— Rethinking Our Gift

“Dear Rethinking
“I’m sure that outfits like Ancestry.com and 23andMe would tell you that their results are very accurate, although I’ve known individuals who’ve sent their little tubes of spit to different companies and have received widely varying estimates of DNA percentages in return. But that’s not really the point here. The point is your elderly mother’s anguish. I fully endorse your decision to discredit the test results in her eyes. For all intents and purposes, the man who raised her is her real father anyway.”

The problem with this advice is that it shows a lack of understanding about what you get with your DNA results. Although the ‘ethnicity’ results may vary between companies, the actual amounts of DNA you share with your matches is absolutely accurate.

It isn’t clear here how “Rethinking” has arrived at the conclusion that their mother’s father is not her biological father, and that is also part of the problem. How did they come to this conclusion? Ann Cannon should not be offering advice based on such inconclusive information.

Furthermore, if it is ascertained from a DNA test that this person’s father is not her biological father, this is a truth that needs to be dealt with with a great deal of compassion and sensitivity. Simply rejecting the test results is not the way to help deal with the implications of such a complex and upsetting revelation.

Identical Twins Ethnicity

When two identical twins, Carly and Charlsie, did a DNA test with each of the major DNA testing companies, they quite reasonably expected their ethnicity results to be the same. So how did the companies explain why their results were actually different?

One company spokesman admitted, “It’s kind of a science and an art!” Is that good enough? At any rate, in my opinion it shows that the ethnicity calculations are certainly more on the artistic interpretation side!

Nonetheless, it is important to remember that the most significant information of your DNA test is going to be found within your match list, not in your ethnicity predictions.

Read about this story here:

‘Twins get mystifying results when they put five DNA ancestry kits to the test’

Scientific American on DNA ‘accuracy’

This is an excellent summary of the value of DNA testing as it pertains to health reporting, family history research and ‘ethnicity’.

How Accurate Are Online DNA Tests?

I agree with all that Adam Rutherford has to say in this article, in particular his assessment of the value of ‘ethnicity’ predictions:

But to say that you are 20 percent Irish, 4 percent Native American or 12 percent Scandinavian is fun, trivial and has very little scientific meaning. We all have thousands of ancestors, and our family trees become matted webs as we go back in time, which means that before long, our ancestors become everyone’s ancestors.

However, I disagree with his final comment that “DNA will tell you little about your culture, history and identity”. I have helped many people who have questions about their identity based on their search for their family connections, particularly those who do not know who were their biological parents. Also for Aboriginal Australians whose recent ancestors were removed from their Country as very young children and never knew where they came from, identifying ancestors and locating Country is tremendously important for creating as sense of kinship and identity. So knowing where you come from, which can be helped through DNA testing, is very key to self-identity.

Half or Full Siblings

Half or full siblings? Another interesting and informative blog post from Judy Russell about how to tell if siblings share the same parents or just one parent.

Half or Full…

I recently had just such a case of borderline 2018cMs, but found that, if the expected family tree is known, checking the shared matches of the two siblings will generally show if one of their parents is different, because they will have matches in common on one parent’s side but not on the other.


Racial Equality and DNA Testing

This opinion piece from Kenan Malik at The Observer, presents an interesting point of view regarding the way DNA testing can be abused to suit a racial agenda that is not in the true cause of racial equality. Although the article highlights some very valid points about the misuse of DNA testing, I don’t agree with the author’s dismissal of DNA testing as ‘pseudo-science’.

Racial equality once meant tearing down barriers, not doing a DNA test