A friend of mine knew I had been working on my family history and bought me an AncestryDNA kit for my birthday. My results were surprising to say the least. I discovered I’m 35% Native American, 5% African and 29% from the Iberian Peninsula. This has drastically broadened the way I think about my identity and heritage. I feel connected to those parts of the world now and I’m excited to see how far back our records can go.
This is another feature of these genetic-testing sites – they are littered with caveats and disclaimers, forever emphasising that they’re not actual “diagnostic tests” and, if you are really concerned by your results, to seek further advice from your GP or another health professional. As has been pointed out by McCartney, when anything looks serious, ultimately it’s back to the very GP and exact NHS infrastructure that these kits profess to smoothly bypass.
Most of the services we tested use genotyping to read your DNA. Genotyping looks for specific markers in your genetic code. For something like ancestry testing, genotyping is effective because it identifies known variants in your DNA. Scientifically speaking, genotyping’s weakness is that it can only recognize previously identified markers. This is one reason DNA tests’ accuracy relies so heavily on the DNA database size; there must be enough information available and identified genetic variants in the database to recognize new customers’ markers.
In addition to showing geographic ancestry percentages, some direct-to-consumer DNA tests also include insights about physical traits like hair and eye color. With 23andMe, this trait information is mostly available in the upgraded Ancestry + Health kit, but some interesting tidbits can be found in the Your DNA Family report, which is available if you opt to participate in the DNA Relatives service. This report tells you interesting information, such as that your DNA relatives are 32 percent more likely to own a cat or 11 percent less likely to have lived near a farm when they were young. DNA Passport by Humancode offers information about more than 20 physical traits, from appearance to grip strength. Ancestry DNA recently added its AncestryDNA Traits upgrade for $10, and it lets customers who have already taken one of its tests unlock information about 18 genetically influenced traits, including bitter taste perception, freckles and cilantro aversion.
Most of this trait data tells you things you already know, like your hair and eye color, but it is fun to see them compared to your genetic relatives and the world at large. We also found it fascinating to learn more about how these physical traits are genetically determined. For example, finger length ratio is determined by hormonal exposure in the womb, with higher testosterone exposure resulting in a better chance of having a longer ring finger. 23andMe’s Health report for finger length ratio looks at 15 gene markers to estimate your likelihood of having longer ring fingers or index fingers.
As my dad and I have begun to explore our genealogy over the past seven years or so, we’ve found that our family is largely from Spain, which is no big surprise. Colombians have a wide range of ethnicities, which explains why many Colombians, including my mother, have white or fair skin with blue eyes. My dad also suspects we have German ancestry somewhere back there.
The first kit I try is Thriva’s baseline test (£49), which, like all its products, checks your blood. The box arrives promptly enough (containing spring-loaded needles, a little collection tube, antiseptic wipes, plasters, etc), but there’s a problem. The idea is to prick your finger and massage blood into the tube, but I just end up making my fingers sore and what I get out barely smears the top of the phial. Maybe it’s just me, but it turns into a right faff. In the end, I take advantage of Thriva’s service to send someone out to take a sample of blood from my arm.
Our testers took multiple DNA ancestry tests, and the services returned slightly different results for each person. This doesn’t necessarily mean that any one company is more accurate than another. Every DNA testing service uses its own algorithm and data set – different reference populations drawn from different databases. Nacho Esteban of 24Genetics told us, “Ancestry is not an exact science. The top five companies in the world would show very similar results when talking about continents; the similarity is smaller when talking about countries. In regional ancestry, some border regions are difficult to identify and sometimes there may be discrepancies. So we cannot take the information as something 100% sure. But at the end, it gives a great picture of where our ancestors were from.”
This test is not designed to do anything other than provide you with a genetic overview based on your sample. My wife's sample indicated that her heritage was part German and part Scandinavian - no surprises there as we were colonised by both sets of peoples. What has been astonishing are the links which her DNA has established exist and now she is in contact with distant relatives in Australia and Canada (they contacted her via Ancestry messaging system). Their familial connection has been verified through examining their respective family trees. Effectively this test is useful as a tool when combined with the ancestry database of births and death, weddings etc. To maximise the benefits therefore you are likely to have to subscribe to access the database and in My case, with worldwide access, it will cost us (my wife and I can both use it) £99, but there are offers from time to time.
Some services include shipping costs in the cost of the kit; AncestryDNA's $99 fee includes two-way shipping. National Geographic's Genographic Project ships the kits for free, but you have to purchase postage when you send your kit to their lab. 23andMe tacks on a two-way shipping fee of $9.95 for the first kit and $5 for each additional one. HomeDNA includes a prepaid envelope to return your sample and offers three shipping options: $7 for two-day shipping, $14 for overnight, and free shipping that takes 7 to 12 business days. Finally, MyHeritage charges $12 for shipping; if you order two kits, you pay $6, and if you order three or more, you get free shipping.
If the company responsible for running your test is sold, whatever you signed loses significance due to the privacy policies of the company. Despite most of these privacy policies stating they will notify you of any changes, you would have to keep in constant contact with the company to ensure you were actually aware of these changes. The people willing to do this would be far and few between. Unfortunately, even if your name is not located within the database, this does not mean other databases cannot be used to determine your identity. In one specific case, a woman had a DNA test run. She found out she had a half-sibling. Although she was very excited about this news, this type of information would devastate numerous individuals.
Of the 23 pairs of chromosomes in the human genome, 22 are autosomes. Most direct-to-consumer DNA tests look primarily at your autosomal DNA to determine your geographic ancestry percentages. This DNA is a mix of inherited DNA segments – half from each parent. Because everyone inherits at least one X chromosome from their mother, DNA tests often include the X chromosome in autosomal testing, though the X chromosome is not an autosome.
HomeDNA has the simplest DNA extraction process; just swab each cheek twice with a cotton swab, and place the swabs in the included envelope. The National Geographic Genographic Project sent a scraper that you use on each cheek for 45 seconds, and then place in a vial with stabilizing liquid. MyHeritage DNA has a similar process. 23andMe and AncestryDNA require that you spit into a tube up to the fill line (harder than it sounds), and ship it back with stabilization liquid. Most of the services said not to eat, drink, or smoke for 30 minutes to an hour prior to testing to get the best possible sample.
Hi Dianne, First thing first, thanks for your comment. “he only test that can give information about recent relatives ( 5 generations back only) is the autosomal test” – autosomal test is indeed a DNA test that gives you the info regarding your relatives, both from the paternal and maternal lineage. We clearly specified it in the article. Ancestry.com, our best-rated provider, offer this test in their Ancestry DNA test. Regarding the accuracy of the time frame you specified, there is indeed a diminishing marginal utility of accuracy as you go back deeper into the past (generation wise). According to one of our most trusted sources (University College of London), the accuracy is 10 generations back and not 5 as you specified (Please provide a source to your number, so we would be able to check it and revise if needed). 10 generation back is a quite long time span – 300 years (more or less). “The tests that say we are such-and-such % of this or that ethnicity isn’t very accurate because keep in mind, the wars and the spoils of wars that humans have been engaged in forever, mean we all have a mixture of genetic material from around the world” – Indeed, most of our ancestors were mixed due to historical events (wars, migration and etc.), but I don’t find how your statement is connected to the fact that this test is not accurate. DNA test is objective and gives you the naked facts. To conclude,
When we speak, co-founder Hamish Grierson describes Thriva as “a lifestyle brand with medical-grade testing at the back end”, an opportunity for “people to see themselves as consumers rather than patients”. Grierson gives examples of people who have benefited from Thriva testing, sometimes picking up early on serious issues. As for alarming people, Grierson says that Thriva has on-site facilities to discuss results and is intended to be “complementary to the NHS” rather than replacing it: “If there are questions we can’t answer, we’re very clear that people should pick it up with their GP.”