Home Health Glenn Ellis Ellis: Beware of the Ancestry DNA Tests

Ellis: Beware of the Ancestry DNA Tests

By Glenn Ellis

Somewhere in America, there are millions of people who have paid to spit in a tube and have their genetic data analyzed to find out their ancestry. Folks who have newfound pride in being told they are descendants from specific parts of Africa. Some of y’all are even convinced you may even be descendants of royalty, while others are coming to grips with the possibility that they are not as “black” as they thought they were.

Currently dozens of companies are offering the opportunity for us to find out from whence we came, just by sending them a sample of your saliva or a lock of your hair.

This promise provides for many of us, the chance to finally know more about who we are, than that we are descendants of enslaved people. As tempting and exciting as the potential for access to this information can be, it is also filled with a plethora of concerns that most of us would never think about.

The technology and science involved in these tests, like many other things in today’s world, has shot past the understanding of most of us “consumers”. Not to mention, like most other things we neither read, nor understand the fine print on prescription meds; legal documents; bank statements; or most everything for that matter.

Let me point out what’s involved in these tests. Most likely, stuff you never thought about.

Once you send your DNA sample off to the testing company (remember there are lots of them out there), the analysis process begins.

One of the fundamental challenges that we face with these tests, and the results they deliver to, is that we simply don’t understand the complexity of the science of DNA and genetics. We’ve become accustomed to the over-simplification of things in our everyday lives, and we totally disregard the science and technology involved in things like computers; voice recognition (Alexa). We want to do the same thing to DNA Ancestry testing. It actually is a science!

Speaking of science, you do realize that at the very least, a person with a Ph.D. in genetics is required in order to know how to interpret and analyze the DNA data from one of these tests? Did you bother to check on the background and training of the people at the company where you sent your spit? Even then, did you know that a trained geneticist can’t tell you about past ancestry, only what your DNA says about who you are today? Don’t worry, I’ll wait.

I should mention, in case you didn’t know, all human beings are 99.9 percent identical. That means there is only a 1 percent difference between the three billion pairs of DNA strains in you and any other human on the entire planet; no matter what color you (or they) are. This is why a mother can give birth to twins, and they don’t look anything alike. It also means that an African from a small tribe in Kenya may have more common DNA with an Irishman than with a Yoruba Nigerian.

The next point you should keep in mind, once they “run your DNA”, the results are analyzed by comparison with what is known as a genetic reference group. This is the point at which your “percentages” are assigned. You know 43 percent African; 29 percent Spanish…you get the point.

There are a couple of problems at this stage. One is that the reference group that your DNA is compared with is comprised of people who “self-identify” their race or ethnicity when they contribute their DNA to the reference group. It has been long established that race is not a biological factor, it is a social construct. The other issue is that the composition of the reference group keeps changing. The same company that gave you one result a couple of years ago, will most likely give you a different result if you did the same test today. This means that different companies will often, likely, come up with different results.

I would be remiss not to include the health information that many of these tests provide, in addition to your ancestry. This is a very “slippery slope”.

What are you supposed to do with information that says that you are predisposed to Alzheimer’s, cancer, or some other unpleasant disease? In many cases this only creates anxiety and fear and leads some people down the path to becoming a hypochondriac. In others it can promote radical medical procedures for a disease that may, or may not happen.

And lastly, and what I consider most importantly, when you spit in that tube, you are also sending DNA for your children; siblings, and other relatives, to who knows where, for who knows what future purpose.  Did you think about how it may affect them with insurance, jobs, admission to schools? Most recently, we are even seeing law enforcement using these genetic data banks to identify criminals who you probably don’t even know, but the DNA provides a trail that leads to jail. It’s almost like a modern-day version of “snitching”.

As you see, a complex issue, with many concerns. Ancestry tests only use algorithms to see where you most likely fit in, they can’t provide you with a perfect match.
Might not want to get that robe and crown out just yet, your Highness.

Glenn Ellis, is Research Bioethics Fellow at Harvard Medical School and author of Which Doctor?, and Information is the Best Medicine. For more good health information listen to Glenn on radio in Birmingham at V94.9 FM, or visit: www.glennellis.com.