Many DNA databases, including Ancestry, 23andMe and MyHeritage DNA, have family search features, which match your DNA with that of potential relatives. These features help users searching for family, including adoptees and children conceived through sperm donations. Almost every DNA testing service we interviewed for this article had a story ready about how its service facilitated a heartwarming family reunion. Like these from Ancestry, this one from MyHeritage and this one from 23andMe. Because many DNA services also have resources like family tree builders, the tests work in tandem with genealogical research.
In Newman’s view, the genie is out of the bottle with home genetic-testing kits. He says that while the kits could potentially provide data in the future, right now, they lack “clinical utility” – they look at genetic variants that, individually, have a very low chance of predicting specific health risks, as there are too many variables: “It’s like the Opportunity Knocks clap-o-meter, with some people further along the scale, and therefore more likely to get the condition and then people at the other end of the scale, who are unlikely to get it.”
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.
Molly K. McLaughlin is a New York-based writer and editor with more than a decade of experience covering technology. She has tested and reviewed all sorts of software, mobile apps, and gadgets. Before launching her freelance business, she was an editor at PC Magazine, covering consumer electronics, followed by a stint at ConsumerSearch.com, a revie... See Full Bio
In McCartney’s view, enough testing is already done in this country (sometimes too much) and there are issues of regulation and “informed consent”. “People are given very dramatic reasons to have these tests – it could help save your life, it could help improve the quality of your life – but where is the actual controlled evidence that these tests have ever done that? There’s no evidence that says doing these tests makes people become healthier.”
I am not sure how Ancestry get their results. Mine is 49% British and 49% German. This means one of my parents must have been British and the other German. I moved to the UK 15 years ago. But both my parents where German as where my 4 grandparents and my 8 great-grandparents. It seems to me they have rolled the dice and assumed that if you send a sample from the UK you must have British ancestry. No science behind it at all. I could have gone to the oracle at the fun fair.
The companies providing ancestry DNA tests are making most of their money from selling the genetic information as opposed to running the tests. Companies purchase this information to increase the size of their genetic databases. Nearly half the companies selling ancestry information are selling to more than just one company. These are sometimes pharmaceutical companies attempting to understand how specific human genome sections can help develop new drugs. Certain mutations will impact the effectiveness of these drugs. The original DNA sample is only destroyed by roughly ten percent of these companies. Most companies keep or sell the sample. This means it is both your data and saliva being sold.