How "precise" is 23andme?

November 28, 2016 1:36 PM

My husband is curious about 23andme, and I'm thinking of buying him and me a kit for Christmas. What could we really learn from it?

We're interested only in the ancestry portion, not in finding out which of many genetic diseases is going to kill us. However, he is 100% French, and according to reliable research I am your typical Euro-mutt American with British, German and a few other very white countries thrown in there.

For those with European ancestry, do the results drill down to specific locations regions, or will he receive a vague "100% French and German" result, with no more details? If that's the case, it's not worth it. Barring some *really* unexpected news, can 23andme (or similar DNA tests) tell us anything we don't already know?

posted by Liesl to Science & Nature (13 answers total)

Short version: You'll basically just get "European", yeah. It's simply not possible to drill down much further than that given our understanding of genetics, and may not ever be possible, since genes don't actually vary as much as you might think by region.
posted by tau_ceti at 1:53 PM on November 28, 2016 [2 favorites]

I pretty much got exactly what i expected (in the "european" space), but I still think it's interesting. Check your memail in a few minutes - I'll send you a few screenshots of the sort of detail it gives me.
posted by brainmouse at 1:56 PM on November 28, 2016 [1 favorite]

I did 23andme a while ago, and my ancestry report doesn't get too specific; my DNA is 37% "Broadly Northwestern European." The few places where it drills down a little further are because those regions are more genetically isolated - e.g. I have bits of Finnish and Sardinian.
posted by Metroid Baby at 1:59 PM on November 28, 2016

Genetic genealogy is best used to answer very specific questions, "are these two people related", and the like. Figuring out countries of origin is best done by documentary research. If you've never done any genealogy, it would be much more effective to buy something like a year's Ancestry subscription. Lots more fun too, as you can build a shared hobby around it, use it as an excuse to take trips, and connect with older family members.
posted by Emma May Smith at 1:59 PM on November 28, 2016 [4 favorites]

If you do the genetic test through Ancestry they will notify you of 4th cousins you've never heard of that are also on Ancestry.
posted by COD at 2:19 PM on November 28, 2016

My dad's 23andme results were so boring I have now taken to telling him he has the world's most boring DNA. (99.9% british/Irish). My mom's however was fascinating and gave us a lot of results we weren't expecting at all including Native American and Asian ancestry. But most exciting she was matched up with some second cousins she had never met and they got to chatting and are now friends on Facebook and my mom has a bunch of new cousins she would have never known otherwise. They are even planning on meeting up.
posted by ilovewinter at 2:34 PM on November 28, 2016 [6 favorites]

I'd do it just to see what % (1-4%)Neanderthal came up on the report!
posted by CoffeeHikeNapWine at 2:56 PM on November 28, 2016 [6 favorites]

23andMe can't drill down past "French and German" for the reasons tau_ceti mentioned, but even someone who's 100% French might have small traces of other populations in it for reasons of historical migrations, etc. etc.

So for example, my family's understanding of my ancestry is that I'm 100% British, German, and Eastern European (I can drill down to percentages of British and Irish, French and German, etc.). 23andMe, however, also lets me know about my 8.9% Ashkenazi heritage and my 1.7% Southern European (including 0.2% Italian) heritage. Who knew?

I also like that it can tell me, in a cool visualization, which parts of each of my chromosomes came from which populations.

Other ancestry features I've liked have been their maternal/paternal haplogroup information and relative sharing (like ilovewinter mentioned).

My favorite ancestry part is probably seeing generational differences. My husband and I, our parents, and my grandmother have all had the test, and it's cool to see which parts of our DNA came from which of our parents/grandparents. If we have kids, we'll totally want to get them tested to see which bits of their DNA came from him and which from me.

MeMail me if you want me to send you screenshots.
posted by bananacabana at 3:12 PM on November 28, 2016 [1 favorite]

If you get 23andme data you can upload it to dna.land which will give you an ancestry view that looks like this screenshot.
posted by grouse at 4:17 PM on November 28, 2016 [3 favorites]

The one for my wife and me did drill down past 80% north European into specific British, German, Swedish components, etc. A few surprises that my family always claims all eight great-great-grandmothers were full-blooded native American. That may have been the case, but actual Native American DNA percentage for me was only 1.5%. Also around 1% Sardinian, which we have no family history legends of. Like others, if you like, I can email you a screenshot of my breakdown.

We're interested only in the ancestry portion, not in finding out which of many genetic diseases is going to kill us.

I would have said the same thing before the test. Today, four years later, it is 20 to 1 the DNA information that gets used the most. The medical stuff is really useful and not depressing. Nowhere in the hundreds of pages of information they provided to us (we are grandfathered before the recent changes made by the FDA) does it say we are going to die of something. It does say interesting things like, "Based on your DNA, we would expect you to have blue eyes," (I do) or "We predict based on DNA you will have light blonde hair which will darken dramatically with age, and which will be straight but have a slight wave if you let it grown long" (all true). 23andme also is continually refining the genome analytics, and producing new finds, for instance they say they recently pinpointed which gene makes a person hate the taste of coriander/cilantro. And some of the medical information is useful, too-- DNA analysis suggests my wife has a resistance to certain types of anesthesia, which would have been great to know ten years ago when she had to be re-hospitalized for extreme pain after her gall bladder was removed. It says I am at an increased risk for diabetes, which lets me alter my lifestyle before my metabolic system crashes past the point of return.

Also, it is kind of funny to know how much Neanderthal DNA you have. I have 5%, which apparently is pretty high, so I announced to my wife that for ancestral reasons I am now allowed to talk like a caveman whenever I want.
posted by seasparrow at 5:37 PM on November 28, 2016 [7 favorites]

You can also upload raw data to Gedmatch.com.

Fun!
posted by jgirl at 7:14 PM on November 28, 2016 [1 favorite]

I think 23andme is very interesting (and yeah, I'm also 99% irish/british, and was also hoping for something more specific), but most of the things that I find cool about it are due to the fact my mother and father also did it, so we can compare our reports. For example, I have a higher percent of Neanderthal than either of my parents, which they think is hilarious. If it was just me alone I don't think I would find it nearly as fascinating. It's obviously three times as much money, but if you can convince his parents to do it if they are alive/good relationship/not weirded out by the idea of it, it is pretty darn neat.
posted by gatorae at 8:19 PM on November 28, 2016

I keep trying to get my dad to do it, but even with the kit in hand he's resistant to the spitting process. As a woman, (no Y chromosome) it can't tell me what genes are from my mom and what are from my dad like they can tell a man. With my dad's DNA, they would be able to tell me. So maybe get your dad to do it too if that is an option.
posted by cecic at 9:04 PM on November 28, 2016 [3 favorites]