Your genetic family tree is not the same as your genealogical pedigree–and not just because of non-paternity events and adoption. Here’s how.
Your genealogical pedigree, if you are diligent or lucky (or both!) can contain hundreds, even thousands of names and can go back countless generations. You can include as many collateral lines as you want. You can add several sources to your findings, and these days you can even add media, including pictures and copies of the actual documents. Every time someone gets married or welcomes a new baby, you can add that to your chart. In short, there is no end to the amount of information that can make up your pedigree chart.
Not so for your genetic pedigree.
Your genetic pedigree contains only those ancestors for whom you have received some of their DNA. You do not have DNA from all of your ancestors.
You do not have DNA from all of your ancestors.
Using some fancy math we can calculate that the average generation in which you start to see that you have inherited zero blocks of DNA from an ancestor is about seven. But of course, most of us aren’t trying to figure out how much of our DNA we received from great great great grandma Sarah. Most of us just have a list of DNA matches and we are trying to figure out if we are all related to 3X great grandma Sarah. So how does that work?
Well, the first thing we need to recognize is that living descendants of Sarah’s would generally be our fourth cousins. Again, bring in the fancy math and we can learn that living, documented fourth cousins who have this autosomal DNA test completed will only share DNA with each other 50% of the time.
Yes, only half.
Only half of the time your DNA will tell you what your paper trail might have already figured out: that you and cousin Jim are fourth cousins, related through sweet 3X great grandma Sarah.
But here’s where the numbers are in our favor. You have, on average, 940 fourth cousins. So if you are only sharing DNA with 470 of them, that’s not quite so bad, is it? And it only takes one or two of them to be tested and show up on your match list. Their presence there, and their documentation back to sweet Sarah, helps to verify the genealogy you have completed. It also allows you to gather others who might share this connection so you can learn even more about Sarah and her family. Plus, if you find Jim, then Jim will have 470 4th cousins as well, some of which will not be on your list, giving you access to even more of the 940.
This genetic family tree not matching up exactly with your traditional family tree also manifests itself in your ethnicity results, though there are other reasons for discrepancies there as well. Read this article to learn more about why ethnicity results may not match.
In short, this DNA stuff is not a stand alone tool, but if you combine it with your traditional resources, it can be a very powerful tool for verifying and extending your family history. Remember, just because a cousin doesn’t show a match in DNA, it doesn’t mean there isn’t a genealogical connection! Genealogical research and primary sources can still prove connections even if DNA doesn’t show it.
Ready to learn more?
My goals as Your DNA Guide here at Genealogy Gems is to help you get the most from your DNA testing efforts, and to make it fun and easy-to-understand along the way. I’ve got more DNA articles for you. Check these out:
Listen to Lisa Louise Cooke’s interview with Ancestry’s Chief Scientific Officer, Catherine Ball, on how your DNA and pedigree chart can work together to reveal your family’s migration story:
Sometimes history provides us with a situation that is just too outlandish to be false, like this one on mDNA testing for genealogy by using ancient ponytails! In these lucky, true-to-life conditions, clues to help us unravel genealogical mysteries and tell our own crazy stories might just be found.
English Mutineers Create Endogamous Population
By Trailer screenshot (Mutiny on the Bounty trailer) [Public domain], via Wikimedia Commons
Do you know the story of the mutineers of the British HMS Bounty? Rewind back to the year 1789, three weeks into the 10-month journey to deliver their cargo from Tahiti to Jamaica. Twenty-five crew members, led by first mate Fletcher Christian, ousted their captain and loyalists. Then, they turned back toward the Tahitian paradise where they had spent the previous 5 months. For their crime of mutiny, they were hunted down. While 16 were later captured in Tahiti and returned to England, 9, including Christian, hid on the tiny island of Pitcairn.
And when I say tiny, I mean tiny. 1.75 square miles tiny.
But considering that 9 English mutineers, their Tahitian brides, and a couple Tahitian men were the founding population for this island, it provides an amazing genetic and genealogical view into endogamous populations.
The Proof is in the Pigtails
This fascinating tale is about to get richer, as ten pigtails of hair claiming to be from some of the original mutineers and their wives, have recently been acquired by the Pacific Union College’s (PUC) Pitcairn Islands Study Center in California. The King’s College London has contracted them to perform DNA testing.
Pay close attention to this next part: Researchers are going to conduct DNA testing on the hair samples. But this does not mean you are going to be able to test the locks of hair stowed away from one of your ancestors!
Why, you ask?
First barrier:Cost. This process of trying to extract DNA from a hair sample, especially a very, very old hair sample is meticulous work. It will cost the average consumer a pretty penny. And, you may not be able to find a DNA testing company who wants to do it for you. All major genetic genealogy companies will just flat out tell you “no.” Most paternity testing companies will require your hair has the root attached. In fact, in my quick search, I can’t even find one DNA testing company that will attempt to get DNA from your lock of hair.
Second barrier: Results. Even if you could get a lab to extract the DNA for you, the only available DNA type retrieved from a cut piece of hair is mitochondrial DNA (mtDNA). The mtDNA will trace a direct maternal line. This is opposed to the YDNA that traces a direct paternal line and the autosomal DNA which traces both sides of your family tree. Even if they do get mtDNA from your sample, it is likely to be damaged and incomplete. Therefore, the best you will likely get is an assessment of your deep ancestral origins.
For you, that might not be quite enough to determine and document your family history. But for those interested in verifying this story of mutineers settling in the Pitcairn islands, it might be.
Will it Work?
If they do get mtDNA from the 10 pigtails, they will get 10 mtDNA lineages represented. Those stemming from the mutineers should have their deep origins in Europe, while their Tahitian brides will have a very different mtDNA signature. Likewise, if an mtDNA signature can be obtained, then the mtDNA of those still living in Pitcairn and nearby Norfolk (where many went in 1857) should match these pigtails. If it does, they can measure how many of the current residents are directly maternally related. Of course, in order to truly verify the claims, some serious genealogy work must be completed.
I will be watching this story closely over the next few months as research progresses. If successful, this will be another victory for the rarely celebrated mtDNA. This study shows that if your goals are understanding deep heritage, or testing out a particular hypothesis on your maternal line, mtDNA can be a useful option.
While the DNA studies you read about in the paper won’t always be something you can learn from, others are. Take for example the stories I shared several months ago on the Genealogy Gems podcast and blog about DNA confirming the love affair of President Warren G. Harding and the story of how experts proved it was King Richard III buried under that parking lot. You can definitely learn about using DNA for genealogy from these very public examples!
These genealogy sleuths used Facebook for family history when they responded to a plea to help return a family Bible to its family.
Back on March 21, Donna Whitten posted a video on her church Facebook page. Her post says, “How far would you go to get back something you’ve lost?”
She was talking about a 150 year-old family Bible she’d come across while antiquing one day in Chattanooga, Tennessee. Her post says, “We want to find this family and return it to them! Can you help?” (Click here to see that post and video.)
That video post got 34,000 views, thanks in part to more than 600 people who shared it! Family history fans immediately stepped up to the challenge. They looked for names on Ancestry.com and reached out to tree owners. Within two days, several descendants were aware of the Bible and asking for copies. The bible eventually went to a woman in California named Carrie Robinson, who has been researching her tree for several years. It contained obituaries clipped from newspapers and handwritten vital family events. (Wouldn’t you love to receive that kind of family treasure?) Click here to watch the follow-up video about when Donna took the bible to the new owner.
Hats off to Donna and her team of sleuths who took the time to find Carrie’s family and return their past to them! I find a few take-home messages in this story:
Social media is a great way to cast your net wide, not just when you’re sharing family history, but when you’re looking for information. Click here to read more about gathering memories through Facebook.
You can watch for orphaned heirlooms in your path and return them to descendants. Click here to read tips on how to do that.
The video Donna created got attention on Facebook! Video is powerful. Use it to share your family history. (Full disclosure: This post contains affiliate links and I will be compensated if you make a purchase after clicking on my links. I appreciate you using these links because that compensation helps make the Genealogy Gems blog possible. Thank you!)Click here to read about Animoto, a DIY-video making service I love that lets you produce your own professional-quality videos. Below is one quick video I created. Can you say shareable?!
When my kids were little I would pack away some of their mountain of toys. Then every so often I would bring them back in to “play circulation” and pack up another batch. To the kids, it was like getting brand new toys!
Our recent move has been sort of like that. As I unpacked boxes of bubble-wrapped baubles it was like finding new family heirlooms all over again.
One example is quite small: a single vintage clip-on earring.
It belonged to my beloved Grandma Burkett. Even though it had lost its match long ago, I couldn’t bear to part with it. As I unwrapped the seemingly useless single earring I was immediately struck with how I could use it. I clipped it in my hair at the end of my french braid!
family heirlooms
Later that day I went shopping with my daughter, and several people stopped to compliment the jewel and inquire about it. When I explained it originally belonged to my Grandmother, faces lit up and family history conversations started to flow. All from one little thing…
Your challenge this week: Look at what you have with fresh eyes, and share your family history with the world in little ways!
Are you attending the National Genealogical Society (NGS) conference in May in Virginia, USA? You’ll want the new2014 conference app, now available for iOS, Android, Blackberry, Windows Phone, and web-enabled devices. (Need a 5-minute video tutorial on using the app? Click the link above, then click on the App Video Tutorial.)
With the NGS 2014 app you’ll be able to receive breaking news, synch your schedule across multiple devices, connect with other attendees, plan which vendors to visit and more. Speaking of the vendor hall, stop by my booth (#618) early, say hello, and pick up my exclusive schedule of quick classes I’ll be offering free at the booth!
I’ll also be teaching these classes:
Google Search Strategies for Common Surnames
Tech Tools that Catapult the Newspaper Research Process into the 20th Century
Find Living Relatives Like a Private Eye
Looking for more info? Here are some helpful URLS:
Your genealogical pedigree, if you are diligent or lucky (or both!) can contain hundreds, even thousands of names and can go back countless generations. You can include as many collateral lines as you want. You can add several sources to your findings, and these days you can even add media, including pictures and copies of the actual documents. Every time someone gets married or welcomes a new baby, you can add that to your chart. In short, there is no end to the amount of information that can make up your pedigree chart.
But here’s where the numbers are in our favor. You have, on average, 940 fourth cousins. So if you are only sharing DNA with 470 of them, that’s not quite so bad, is it? And it only takes one or two of them to be tested and show up on your match list. Their presence there, and their documentation back to sweet Sarah, helps to verify the genealogy you have completed. It also allows you to gather others who might share this connection so you can learn even more about Sarah and her family. Plus, if you find Jim, then Jim will have 470 4th cousins as well, some of which will not be on your list, giving you access to even more of the 940.
My goals as Your DNA Guide here at Genealogy Gems is to help you get the most from your DNA testing efforts, and to make it fun and easy-to-understand along the way. I’ve got more DNA articles for you. Check these out:
These genealogy sleuths used Facebook for family history when they responded to a plea to help return a family Bible to its family.
That video post got 34,000 views, thanks in part to more than 600 people who shared it! Family history fans immediately stepped up to the challenge. They looked for names on Ancestry.com and reached out to tree owners. Within two days, several descendants were aware of the Bible and asking for copies. The bible eventually went to a woman in California named Carrie Robinson, who has been researching her tree for several years. It contained obituaries clipped from newspapers and handwritten vital family events. (Wouldn’t you love to receive that kind of family treasure?) 
