In , the company launched the African Genetics Project , offering free DNA kits to people with all four grandparents born in the same African country, or from the same ethnic or tribal group.
Now it has launched the Populations Collaborations Program , which encourages researchers studying remote populations to submit their data to the website. But questions have been raised about the ethics of European and American scientists harvesting genetic information from Africans and African scientists for economic gain.
Users are asked if they want to participate in scientific research when they sign up. Privacy is a major concern for everyone using these sites, but perhaps more so for those from minority backgrounds. For those who are already discriminated against, having their genome used against them — for example, in the criminal justice system — could have serious implications.
An internal report revealed that in , AncestryDNA received 34 law enforcement requests, and provided information to MyHeritage asks customers to email if they want their sample removed from its database, though a representative tells me that the company does not sell or share DNA data with third parties.
In , to illustrate the privacy risks, researchers from the Whitehead Institute for Biomedical Research in Massachusetts identified nearly 50 people who had participated in an anonymous genomic study, based on publicly accessible information.
T here are many scientific limitations to the home DNA test. There are a few reasons for this. First, the genetic information these DNA testing companies hold is based on living populations. When you send your spit off in a little tube, it is specific snippets, or markers, in your genome the total collection of DNA that resides in your cells that are being analysed, and then compared to the markers of others who are good representatives for distinct regions or ethnicities around the world.
But as Thomas notes, the companies are only looking at very recent samples, from a relatively small group, in one specific database. The databases are skewed towards different parts of the world, too. And by the time you go 10 generations back, there are ancestors from whom you inherit no DNA. Evolution is not acting fast enough to create any substantial changes.
There might be a lot of genetic markers Nigerians share, for example, but that are not necessarily exclusive to them. But there have been some bizarre cases of failure, such as the company that failed to identify the sample DNA as coming not from a human, but from a dog. Almost every DTC genetic test does not sequence your entire genome, but instead looks at positions in your DNA that are known to be of interest.
When I was tested by 23andMe, they proclaimed I do not carry a version of a gene that is associated strongly with red hair. Another ancestry company said I did. This merely reflects the fact one company was looking at different variants of the gene that code for ginger hair. If we assume the data generated is accurate, then the second question that arises is on the interpretation. And this is where it gets murky.
Take a bunch of people, as many as possible, that have a shared characteristic. This could be a disease, like cystic fibrosis CF or a normal trait, say, red hair. When you sequence all their genes, you look out for individual places in their DNA that are more similar within the test group than in another population.
For CF, you would see a big spike in chromosome 7 because the majority of cases of CF are caused by a mutation in one gene. But for complex traits like taste or ones relating to diet or exercise, dozens of variants will emerge, and all of them only offer a probability of a predisposition toward a certain behavior as a result of your DNA, as measured in a population. This even applies to something as seemingly straightforward as eye color: A gene variant that is associated with blue eyes is still only a probability that you will have blue eyes, and it is perfectly possible to have two blue-eyed genes and not have blue eyes.
When it comes to ancestry, DNA is very good at determining close family relations such as siblings or parents, and dozens of stories are emerging that reunite or identify lost close family members or indeed criminals. For deeper family roots, these tests do not really tell you where your ancestors came from. They say where DNA like yours can be found on Earth today. By inference, we are to assume that significant proportions of our deep family came from those places.
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. They also offer the possibility of connecting with potential relatives based on matches in your DNA to other users in their database. It is this disease risk assessment that got the company into some trouble with the FDA back in At the time, the Food and Drug Administration required that 23andme discontinue the disease prediction portion of their service until they could offer more proof of the accuracy of their tests as well as evidence that their customers understood their results.
However, as of April , the FDA has restored authorization to 23andme to provide the information on genetic disease markers based on evidence from peer-reviewed scientific studies directly linking those diseases with the genetic mutations the company tests for.
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