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Tag: 23andme

The Problems with Ancestry Tests (23andMe,, etc.)

Over the past five years or so, ancestry and DNA tests have risen in popularity due to people’s desire to find out what medical conditions they are at risk for, or where their ancestors are from.  The most common concern I have heard about as a result of these tests was that the companies would sell your DNA to third parties or the government (while there is a chance this could be true this will not be the focus of this article).  However, the true problems are not conspiracy driven, yet they are scientifically driven and verifiably true.

Many people using these tests do not realize how these tests actually work and the wrong information they present at times.  The first issue resides in the health screenings of these ancestry tests.  They claim to use your ancestry to see if you are at risk for Alzheimers, certain types of cancer, Parkinson’s, or what type of body type you have.  These companies are not completely lying, however the tests can omit certain things and it is no substitute for going to an actual doctor.

Everything they search for is compared to a reference population, therefore your genes are merely compared to other people who are considered healthy or unhealthy.  These tests do not have access to medical history in order to look for other clinical factors that could accelerate or further exacerbate this potential condition, thus explaining why it is irresponsible to tell people they are at risk for a debilitating disease because someone with similar genetics reported developing a disease that could have resulted from his or her specific lifestyle.

The issue with self-reporting in ancestry tests also can be seen in testing for heritage.  The data these companies use are based off of reference populations (many of which are self-reported especially in the early years of the tests), therefore the same person can receive different results at different times.  The database is constantly changing (which isn’t necessarily only a bad thing) so if the same person takes the test three times in three different years, they are likely to get different results.  If the company recently expands to selling DNA kits in a new area of the world, a person with mixed heritage from the United States can receive different results because the test population of a certain region was extremely small and unspecific before, whereas now they have more of a test population that can change “how Vietnamese you are” (or whatever region that applies to you).

Have you ever known someone who took the DNA test and found out they were not as Greek or Russian (insert anything) as they thought they were? These results are problematic on so many levels when breaking down ancestry.  The first example is that when comparing extremely similar populations, your heritage might not reflect your ancestry that the test finds.  For example: modern English, Scottish, and Irish people have vastly similar results in these tests because they are very similar genetically and geographically, therefore a person can find out they are 50/50 Irish and English, however all of their known relatives can be traced back to 1870s Ireland.  The person is not “less Irish than they thought”; it merely means that centuries of migration and conquering in the region of the British Isles could blend the gene pools even if this person’s family tree of the last two-hundred years can be traced back to one specific town.

Something else important to consider is that ancestry and heritage are not nearly synonymous terms.  Furthermore, two twins could receive different genes from the same parents which could lead to slight changes in genetic makeup.  Your sibling is not “more Swedish than you” in terms of heritage and the culture you were raised in.  The sibling might receive a certain gene from your parents that you did not.

While there are a myriad of problems and hypotheticals to bring up, I will leave you with one last problem. Groups of people that live in diaspora such as Jews, Romani, and Armenians could have problems with these tests.  Ashkenazi Jews from Eastern Europe live in diaspora and have been a migratory group for centuries, leading them to mix in with various gene pools that they settle in.  When an Ashkenazi Jew or Romani (who similarly lived a migratory history) takes an ancestry test, they could feel completely related to their Ashkenazi or Romani heritage, however the intermixing of people over centuries (because they settled in so many places) could come up in the test even though they feel like they have no relationship to the heritage at all.  Romani people also are difficult to pinpoint to one specific region of origin which demonstrates another potential problem with the tests.

While these tests can be a fun activity to do with your friends, make sure you take the results with a grain of salt because you are not necessarily  “less French than you thought”.


23 Chromosomes. One Unique You.

This weekend, my parents told me we were trying a new product from a company called 23andme. When I first saw the words ”Welcome to you, DNA Collection Kit” written on the box, I thought it was another one of my Dad’s SkyMall purchases that is thrown away a week after buying it. This one was more intriguing than most, so I decided to investigate on-line. I am amazed that he actually purchased something of use.

23andme is a new company that analyzes your DNA and compares it to millions of others to determine your unique traits. While human DNA is about 99.5% identical between people, there are small differences called variants. These variants come from your parents, your parent’s parents, and so on. Within a month of submitting your DNA, I will get results that will tell me a number of things relating to my genetic make-up including possible health conditions that I have now or will get in the future, traits and my ancestry groups. I can’t wait.

To start the process, 23andme provides a tube with instructions. I had to spit inside the tube and my saliva was mixed with a clear liquid when I sealed the tube.  The tube is then shipped to 23andme, where they will take the saliva sample and extract and process the DNA on a genotyping chip that reads hundreds of thousands of variants in your genome. Genotyping is a method to extract and analyze the DNA found in your saliva. The lab will read the variants in my DNA versus other people’s DNA and generate personalized reports based on well-established scientific and medical research.

I’m pretty nervous about what the DNA test will tell me!

First, I will learn about my ancestry – where did I come from? What percent of my ancestry is European and what percent is Cuban? Who are my relatives? Is Yoenis Cespedes my real father? All of these questions will be answered along with contact information for my DNA relatives around the world- I think this means season tickets too!

Secondly, I will find out if I am a carrier for certain inherited conditions. Being a carrier means I have the variant for a condition which I can pass down, but I don’t have the condition. This is where potential controversies arise because people may or may not want to know if they are carriers  for harmful diseases. I am not sure I want to know! They test for over 35 conditions.

Thirdly, I will get a report that explains how my DNA impacts my health and my traits. Some of these include hair color, my chances of having a unibrow,  if I’m going to go bald (and when!), and if I have a preference for sweet vs. salty foods (I actually like both so good luck with that!).

I’m particularly excited for my results because I was born with a syndrome called Beckwith-Wiedemann syndrome, which results from the abnormal regulation of genes in a certain region of chromosome 11. I’m very interested to see if they are able to tell me more about this syndrome.

As 23andme gets more popular, there will be more data to compare with, which will expand the limits of what we can find out! I can not wait to meet all of my DNA relatives. Results will be in by the end of November, hopefully just in time for bring your Father to school day!




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