Monday, June 12, 2006

The Bogus-ness of DNA Testing for Genealogy Research

At this point, pretty much everyone knows, there are many companies out there promising to unlock the secrets of your ancestry and heredity through DNA analysis (a.k.a. genetealogy). If you send them some DNA from a simple swab of your cheek -- and a good-sized chunk of money -- they'll test your DNA and tell you, among other things, what stock you came from: European, East Asian, African, etc.

Several years ago, when these companies first started surfacing, I looked at some of their claims and thought, That sounds sketchy. From what I knew about DNA testing, it seemed like these tests were a scam. So I wrote an article for Popular Science investigating whether this technology, and therefore the companies offering it, were legit. I put together a panel of experts in genealogy and DNA testing, including one of the scientists who first discovered some of the technology many of these companies base their tests on. I had my DNA tested along with the DNA of six of my family members to see if the tests could uncover something you'd never know from looking at me: My grandfather's great great grandmother was black. The companies offering the tests assured me, if that were true, their tests would find it. So I ran the tests. I had my panel of experts investigate the results, then wrote the story, explaining the science of these tests, what they did and didn't find in my family tree, and what the experts say about the legitimacy of it all.

Their conclusion and mine: These tests can be fun, and they have some definite use in medical research, but they simply can't tell you anything definitive about your heredity unless you're testing your DNA and comparing it to someone else's to find out if you're related. These tests most certainly can't tell you what you're not -- as in, you're not African-American.

But the general public doesn't know this, and no one seems to be telling them. More and more of these companies are popping up, the popularity of these tests has soared, and every month or so, a journalist (like this guy today) writes yet another story about how people are using this technology to unlock family secrets and "debunk family tales," even though it simply doesn't work that way. The upshot of so many of these stories is that people are being confused or traumatized by results from these tests. People with dark skin who came from black families and identified themselves as African-American are suddenly being told that they aren't African-American at all. People have sought psychotherapy over these results and questioned their families. But this is all based on a science that can't actually say you're not African American, (and most certainly can't say you're not Caucasian and therefore should qualify for minority scholarships and affirmative action).

There have been a few good stories about the realities of DNA testing for genealogy research, but unfortunately, the ones people see (and hold on to) are the ones that tell them what they want to hear. It's maddening.

Don't get me wrong, I'm completely in favor of DNA tests showing that deep down, we're all the same -- that black, white or tan, we're all a mish-mash of genes and race is a "social construct," not a genetic one. What I'm not in favor of is this: Companies using that fact -- along with the public's undying curiosity about ancestry -- to make promises they can't keep (like, we'll help you find long-lost relatives), while turning a good-sized profit off delivering results that cause mass confusion. And journalists helping them do it.

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Blogger Jason Presley said...

I'm so glad you wrote this. Watching all the recent programs on television about DNA testing and people "connecting" with their ancestral homelands has really annoyed me. Almost universally, the subjects on these shows latch onto the single result they're given as if that is the only ancestor they're descended from. And then there are the more famous results like Oprah Winfrey being crushed to find she wasn't descended from a Zulu ancestor.

Well, unless I'm missing something, when I had my DNA test done, the package explained that, as a man, I could be tested ONLY for my direct paternal and direct maternal lines. As a woman, Oprah could only be tested for her direct maternal line. Meaning, out of the 128 ancestors she had just 7 generations ago, she could only be tested for one of them. So all the test confirmed was that ONE of her SIXTY-FOUR 5th great-grandmothers wasn't Zulu or descended from the Zulu tribe.

That's 1 out of 128. And don't forget, every generation back you go, theoretically, the number of your ancestors doubles since everyone has two parents. Sure, in many family trees, somewhere there are duplicated ancestors because different ancestors inter-married, but that's still a LOT of ancestors to that single DNA result.

10:48 AM  
Blogger Rebecca Skloot said...

Here's an interesting article about the only kind of DNA testing that can actually fill holes in the family tree: The kind where you're trying to match actual people. And this effort is pretty amazing.

9:32 PM  
Anonymous Anonymous said...

I came across your blog while researching DNA testing and greatly appreciate your prespective. I will keep it in mind as I reflect on the results of my DNA testing which I plan to do every couple of years as the testing becomes more refined. While these tests are not completely inclusive of all relevant ancestral markers, they are an important first step for many. As an African American, DNA testing provides far more information than I ever thought would be possible in my lifetime.

But what I am really writing you about is that I was guided to your captivating article "Henrietta's Dance." What a complex and disturbing story and very well written. When can we expect to see your book?

5:04 PM  
Blogger Rebecca Skloot said...

How strange, a comment I posted a while ago responding to Jason's post seems to have vanished. Blogger is mysterious sometimes.

The gist was this: I'm glad people are finding my post and article helpful. It's been frustrating at times to watch how these tests are embraced as being definitive (even by people like Oprah). I agree with Fortune, who pointed out that these tests do offer at least some glimpse into a genetic past that most African Americans never even dreamed could be possible, since so much of the paper-version of that history was destroyed by the institution of slavery. I just think it's important for people to understand what information they're actually getting. But that doesn't seem to be happening -- these tests have a strong and sometimes painful impact on people though it's clear that the science simply isn't there yet.

As for my book, Fortune: I'm glad you found and liked the story about Henrietta Lacks and the HeLa cells. My book will be in boookstores in 2007 -- I will most definitely post updates and announcements about it here on my blog.

5:25 PM  
Blogger Rebecca Skloot said...

For those who are curious, you can read "Henrietta's Dance," which Fortune mentioned above, and several other articles related to my book on this page of my website.

5:29 PM  
Blogger Travis LeMaster said...

Great article! It summarizes my problems with the whole DNA craze in genealogy.

10:36 AM  
Blogger langolier said...

What ARE your problems, Travis?

6:27 PM  
Anonymous Anonymous said...

Anyone who sought therapy for whatever DNA testing told them probably needed therapy to begin with anyway.

4:29 AM  
Anonymous Anonymous said...

Dear Rebecca,

While your family’s DNA testing may not have revealed any African American ancestry, one of the places it may still lurk is in Elenor’s father’s Y-chromosome. While the census record lists Elenor as being “white”, see:
That does not mean that she wasn’t African American as her father may have been and those results might not show up in your autosomal test since its several generations back.

I feel that the “problem” expressed, is that there’s no “magic pill” type of test where someone can take one test and their entire heritage will be revealed. When I first learned about this testing in 2003, I did not initially grasp that concept and was a bit disappointed when I understood the limitations. However, I made a proposal for Y-chromosome testing to a family group of researchers, and this led us to uncovering several 200+ year old mysteries. One of those mysteries was whether a line in Virginia was related to our line in South Carolina, and testing (along with documentation) has confirmed this. This is exactly why DNA companies can make those claims on their website, “of finding long-lost relatives” because indeed you can! We are sixth cousins that are as close as first cousins.

Genetic genealogy would not have such a surge in popularity if it DIDN’T work. The only thing “bogus” about it is false expectations.

1:48 PM  
Blogger Rebecca Skloot said...

The census records don't actually list Elenor as white -- they list the other women who'd lived in her husband's house as being white. He was married twice, first to a white woman, then to Elenor. The white women in his house were his first wife and their daughters. While I'm flattered that someone took the time to look into my family history to prove my story wrong, she didn't actually find anything different from what I reported (in my story, I said Elenor was my grandfather's great great grandmother -- that doesn't leave off two greats as my critic claims, it just phrases them differently because I didn't want to say she was my great-great-great-great grandmother, because it's wordy). No matter: In the end, we actually don't disagree about genetic testing: From what I can tell, we both think that using genealogy for genetic research is oversold to the public and overhyped by the media, and that buyers should educate themselves so they understand what they can get out of it, so they aren't expecting something the science can't deliver.

As I said in my post and in my article, testing of the kind you did -- comparing two family lines by comparing DNA samples -- is completely legit, and does lead to answering questions about whether people are related. But sending a sample of your DNA in to a company that says they'll tell you your ethnicity or find lost relatives by plugging your DNA into a database is something entirely different ... that's where promises start exceeding what's scientifically possible. And that's what's bogus. Consumers have false expectations when it comes to those tests because they're being offered something that's not scientifically possible.

10:26 AM  
Anonymous Anonymous said...

I am an applied biocultural anthropologist, "African American" (politically and socially, but help me out here if looking for my bone marrow) and I have been dealing with some of these issues for quite a long time. Let me share some of my thoughts. (1) There was a time when it was chic to have a Cherokee princess grandmother, now it's Edward Ball's, "Slaves in the Family," that's the going craze. (2) Many of the scientists who have worked on the Human Genome Project and are faced with the clear scientific aspect that we're all "Out of Africa," don't have a problem with 100,000 years out --the problem creeps up when it might be their great-great grandfather or G-G mother. That's when things get a bit tight. One has only to witness the sickle cell testing issues in Louisiana in the 1970s. After enough good "white" folks started showing up with Duffy antigens and sickle trait, the political community told the medical community to, "shut that thing down."
(3) I love to talk to colleagues at cocktail parties who are trying to determine if their from "uhuru" village somewhere in the motherland. It would be a lot better if they spent their time donating blood to the American Red Cross so that kids who are suffering with sickle cell disease and who are suffering with silent strokes and are alloimmunized, can get transfused today. That's today, not 400 years ago. Sometimes, it's easier to romanticize the past instead of taking care of business--which includes--medicine, public health and healthcare access now. If anyone wants to chuck a Zulu spear, chuck it into blood diseases, low and no access to healthcare and genetic disorders.
Kathleen Rand Reed

5:56 PM  
Anonymous Anonymous said...

I too am glad to see that SOMEONE is finally speaking up about this testing. I feel a bit ripped off by my husband's recent tests. It didn't really tell us anything we didn't know, and it certainly didn't tell us what we really wanted to know. My husbands dad was of Irish decent, his mother of English. That's what the test "revealed". Although looking at him will tell even the casual onlooker that that is not the whole story! People have been calling him "chief" most of his life. We know that he has African American cousins, but is it on his side as well? Is it Native? jewish? Who knows.... certainly not those who are doing the testing! LOL. We have decided that although it would be fun and interesting to know, it's probably ok to just be enjoy the mystery. When it comes to dna testing, just remember, buyer beware!

10:23 PM  
Anonymous Anonymous said...

Paternity testing is not reliable. It is completely unregulated, and so have no verifiable standards. Sometimes this industry creates their own "standards" by claiming accreditation. But the companies doing the accrediting are just the dna "boys club" once again, private, and so account to no one. If you ask them anything about the maintenance of their equipment, staff training, or error rates, they refuse to answer, and direct you to the labs. Until this industry has a separate, governmental regulatory agency, they are just a private company making money by selling a really interesting parlor trick. As long as people are willing to pay, they don't care who's life they destroy with this joke. The children are their victim's.

2:33 PM  
Blogger NJWEEDMAN said...

Actually DNA testing is great, but I keep noticing that writers who dispute this are JEWISH! Why do they do this? Because the new DNA testing constantly shows people who have historically claimed to be Jewish to actually be European.


I suspect the writer here falls into that catagory! The new dna testing rejects the jewish claim that they are the rightfully owners of Palestine. Most of the Jews in occupied palestine are Europeans who over the centuries adopted the religion of the biblical hebrews but they aren't those people as they claim.

The Biblical Hebrews, the ones that "GOD" gave the land of Cannan too were black. The jews of today are mostly Europeans (white). DNA shows they aren't the biblical hebrws and have no right to the land of Isreal.

1:47 PM  
Blogger Rebecca Skloot said...

Wow, that wins the award for the craziest comment I've ever gotten. The logic behind it couldn't be more off. There is no genetic basis for Judiasm (it's a religion, there are no religion genes). But regardless, if you read the article in question, you'll see researchers of many races and religions explaining why the scientific evidence simply doesn't support this kind of genetic testing yet. That's no conspiracy.

11:59 AM  
Blogger Anonymous said...

I wish I read your article before buying this! I first found out about these tests through the documentary on PBS and decided to give it a try. I purchased one to find out more about my past; the results just confused my family and me. According to my family history my father’s mother’s family came from Northern Spain bordering France and my grandfather from my father’s side was Native American… on my mother’s side her mother’s father was from Spain and her grandmother was half European and half Native American. My mother’s father was of Southern European ancestry. I always thought of myself as a mestiza (a mix of European and Native ancestry). The results showed that I was less than half European a third African some Native American and East Asian. My first thought was ok… did they mix my papers with someone else’s LOL. I started questioning my family and they became very confused. By first glance people think I’m Native American. I am more bewildered now than before I bought the test. I guess the only way to truly find out about yourself is through a paper trail.

11:00 PM  
Anonymous Anonymous said...

Thank you for your very interesting comments. I am actually the administrator of a Y-DNA project, and am surrounded on the discussion boards by people who are very "pro" this testing. I actually am, too, but only under the circumstance that the person being tested truly understands what the test can and can't show.

It is definitely not a substitute for paper genealogy. And as you pointed out very well, a Y-DNA test only shows your "father's father's father" (etc.etc.)

Before starting our project, we spent eight years putting together a computerized database (from church records) of the 5 Bukovina Hungarian villages. There are now more than 80,000 people in the database, and in many cases, it goes back 10 generations or more (from people alive today).

As you pointed out, at ten generations, we are talking about 1024 potential ancestor (and this particular test gives you information about only one of them).

In the case of our project, though, the Y-DNA has been a very good addition to the "paper trail". The church records in Transylvania only go back to about 1700 (at the earliest), so the DNA is the only way to find out whether like-surnamed people have a common recent ancestor.

An since surnames were adopted only about 1500-1600 in this area, Y-DNA can also show that families with different surnames may still have a common ancestor.

Beth Long

7:54 AM  
Blogger Unknown said...

Links to 'interesting article' and 'Henrietta's Dance' do not work.
My sister is claiming that can use DNA to show more than the one-line maternal or paternal link. I don't believe her, and after search a bit on that service and googling, I am sure I (and you) are right.

2:24 PM  
Blogger Rebecca Skloot said...

Thanks for letting me know about the broken links. The link to more information about my book, and Henrietta's Dance, is here. The other story has been taken offling, unfortunately.

4:52 PM  
Blogger 1212 said...

I agree that most of the DNA opponents are Jewish. First of all the people who actually formed the religion of "judaism" were ethnically Hebrew people. The ancient Hebrews were not white or of caucasian origin.
They would be by today's standards of racial classifications considered to be "black". DNA testing now makes that very clear.
The word Jew or Jewish did not exist in ancient times. It was manufactured by Northern and Southern Europeans who adopted the relgion of the biblical Hebrews. They used this manufactured word to obtain a religous identity and in 1948 as a political tool to lay claim to the land of Israel.
Here is the irony in it all though. More and more African Americans that take the DNA test are getting back results that show clearly that the "origin" of their DNA places them in the following Haplogroups: E3a, E3b, and L3 which also places them smack dab in the heart of North and Northeast Africa which includes, Egypt,Ethiopia, and of course Israel. On the other hand Jews are scared to death to take the test because the origin of their DNA reflects common European Haplogroups such as R1b, G2, and H1.which conflicts with their ancestral claims to the land of Israel.

2:51 PM  
Blogger John Mullen said...

Thanks for your piece. My best friend, normally a rational sort of person has gone nuts about needing to find out all about her family history through DNA. Is there a gene for gullible?

7:20 AM  
Anonymous Anonymous said...

Actually, I have a comment for Anonymous. Anonymous, you know your family history better anyone else but it could be possible that the DNA test is correct. Many mixed families of African/Caucasian/Native American descent have dropped off the African part of their heritage because of discrimination and stereotypes. It was easier for a person to be White with a little Indian than to be mainly African/Native American with a little White especially if you are from the South. Also lighter hued African Americans commonly would pass as Whites. You usually hear about families saying that they have Native Americans, Black Irish, and Black Dutch or Portuguese when in fact, they had an African American ancestor that they may or not know about. Of course, the test just could be wrong but it could be a possibility.

2:53 PM  
Blogger Christine said...

What excited me most about the DNA testing was that I thought I'd finally get some answers to my birth father's roots. I was very disappointed to find out that I had to have a male relative from my father's side of the family's DNA for the test. I have sought in vain to find these relatives and am just left to explore the many branches of my mother's lineage. I am awaiting my DNA testing results as I type this. As of yet I have no opinion for or against it.

10:36 PM  

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