From roots-in@roots-l.rootsweb.com Sat Aug 12 20:20:44 2006 Received: from mail.rootsweb.com (mail.rootsweb.com [192.168.65.34]) by admin.rootsweb.com (8.12.8/8.12.8) with ESMTP id k7D2Kijb016470; Sat, 12 Aug 2006 20:20:44 -0600 Received: from roots-l.rootsweb.com (roots-l.rootsweb.com [66.43.16.22]) by mail.rootsweb.com (8.13.4/8.13.4) with ESMTP id k7D2Ke9S008715 for ; Sat, 12 Aug 2006 20:20:40 -0600 Received: from roots-l.rootsweb.com (roots-l [127.0.0.1]) by roots-l.rootsweb.com (8.12.10/8.12.10) with ESMTP id k7CNfBFI003627 for ; Sat, 12 Aug 2006 19:41:11 -0400 Received: (from roots-in@localhost) by roots-l.rootsweb.com (8.12.10/8.12.8/Submit) id k7CNfBYI003626 for roots-approved@rootsweb.com; Sat, 12 Aug 2006 19:41:11 -0400 Resent-From: roots-in@roots-l.rootsweb.com Resent-Message-Id: <200608122341.k7CNfBYI003626@roots-l.rootsweb.com> Received: from lists5.rootsweb.com (lists5.rootsweb.com [66.43.27.41]) by roots-l.rootsweb.com (8.12.10/8.12.10) with SMTP id k7CLn8FI002206 for ; Sat, 12 Aug 2006 17:49:08 -0400 Received: (from slist@localhost) by lists5.rootsweb.com (8.12.8/8.12.8) id k7D0SRsK011261 for roots-in@roots-l.rootsweb.com; Sat, 12 Aug 2006 18:28:27 -0600 Received: from mail.rootsweb.com (mail.rootsweb.com [192.168.65.34]) by admin.rootsweb.com (8.12.8/8.12.8) with ESMTP id k7D0SPjb011247 for ; Sat, 12 Aug 2006 18:28:25 -0600 by mail.rootsweb.com (8.13.4/8.13.4) with ESMTP id k7D0SJen030407 for ; Sat, 12 Aug 2006 18:28:19 -0600 for ; Sat, 12 Aug 2006 17:28:19 -0700 (PDT) Delivery-Date: Sat Aug 12 17:22:32 2006 Received: from askin-67.linkpendium.com (askin-67.linkpendium.com [63.173.235.67]) Received: by askin-67.linkpendium.com (Postfix, from userid 503) id 4F15124B193; Sat, 12 Aug 2006 17:22:27 -0700 (PDT) Received: from roots-l.rootsweb.com (roots-l.rootsweb.com [66.43.16.22]) by askin-67.linkpendium.com (Postfix) with ESMTP id 99E2124B184 Received: from roots-l.rootsweb.com (roots-l [127.0.0.1]) by roots-l.rootsweb.com (8.12.10/8.12.10) with ESMTP id k7C1B3FI030127 Received: (from roots-in@localhost) by roots-l.rootsweb.com (8.12.10/8.12.8/Submit) id k7C1B33E030126 Received: from vms048pub.verizon.net (vms048pub.verizon.net [206.46.252.48]) by roots-l.rootsweb.com (8.12.10/8.12.10) with SMTP id k7BKthFI029610 for ; Fri, 11 Aug 2006 16:55:43 -0400 Received: from l9d2v7 ([71.243.246.48]) by vms048.mailsrvcs.net (Sun Java System Messaging Server 6.2-4.02 (built Sep 9 2005)) with ESMTPA id <0J3U000SFXHUXAF7@vms048.mailsrvcs.net> for roots-in@roots-l.rootsweb.com; Fri, 11 Aug 2006 18:34:43 -0500 (CDT) Date: Fri, 11 Aug 2006 19:34:24 -0700 From: "Derrell Oakley Teat" To: "Roots-In" Message-id: MIME-version: 1.0 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) Content-Type: text/plain; charset="UTF-8" Importance: Normal X-Priority: 3 (Normal) X-MSMail-priority: Normal Sender: roots-in@roots-l.rootsweb.com Resent-To: roots-l@rootsweb.com Resent-Date: Sat, 12 Aug 2006 17:28:19 -0700 X-Scanned-By: MIMEDefang 2.52 on 192.168.65.34 X-Scanned-By: MIMEDefang 2.52 on 192.168.65.34 X-MIME-Autoconverted: from 8bit to quoted-printable by lists5.rootsweb.com id k7D0SRsK011261 Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by roots-l.rootsweb.com id k7CLn8FI002206 Subject: [ROOTS-L] mtDNA Explainations Excellent article to read and learn about DNA Derrell Oakley Teat Ancestry Daily News Megan Smolenyak Smolenyak – 8/4/2006 -------------------------------------------------------------------------- The ABCs of mtDNA by Megan Smolenyak Smolenyak When it comes to genetic genealogy (which I often refer to as genetealogy), Y-DNA is by far the most popular type of testing--and understandably so. Since Y-DNA is passed from father to son down through the generations (just like surnames) its appliccation is fairly obvious. But over time, mitochondrial DNA (usually shortened to mtDNA) testing has been gaining in popularity. How mtDNA Travels Many folks regard mtDNA as the equivalent of a maternal version of Y-DNA testing and while there are some parallels, there are also some differences, and that creates a lot of confusion. For instance, mtDNA is passed down through maternal lines, but mothers pass it on to both their sons and their daughters. The sons, however, become mtDNA dead ends and do not pass it on. This means that a brother and sister (who share the same mother) can both get tested for mtDNA, and that they both can serve as living representatives of their mother, their mother's mother, their mother's mother's mother, and so on. (Think of the bottom line of a pedigree chart). But when this brother and sister pass on, her children will continue to sport the same mtDNA, while his will have his wife's mtDNA. Primarily a Deep Ancestry Tool Perhaps the most important aspect of mtDNA to grasp is that it's essentially a deep ancestry test, and is not as genealogically useful as Y-DNA. If you're familiar with Bryan Sykes's best-seller, The Seven Daughters of Eve, you may recall that the underlying premise is that 95 percent of people of European origin can trace their maternal roots to one of seven women who lived in Europe approximately 10,000-45,000 years ago. I, for example, am from haplogroup H (haplogroups might be thought of as branches of the world's family tree--in this case, the world's maternal family tree), which Sykes dubbed Helena. Her descendants were the most successful in reprroducing. Consequently, roughly 30-40% of those of European origin are also H. And this, in turns, means that I have millions of maternal cousins. That's not tremendously helpful to know when it comes to tackling my family tree. Are You My Cousin? Unfortunately, a lot of genetealogy newbies fail to understand this, so once they get their results, they tend to play the matchmaking game. By this, I mean that they e-mail everyone who matches their mtDNA, share the usual name/place/date details of their direct maternal line back to their earliest-known ancestor, and then cross their fingers hoping for someone to report back having found some overlap. But because it's such a massive fishing expedition, this hardly ever happens. (I know of one success story, and in my mind, this person hit the mtDNA lotto!) Given its limited utility, why would folks even be interested in taking mtDNA tests? One reason is simple curiosity. A lot of people are genuinely interested in knowing about their deep ancestry. So if you want to know roughly when and how your direct maternal line migrated out of Africa, you might take this test to find out. For most folks, this is all they will learn, but for many, it's sufficient. Three Exceptions and... Having just said that mtDNA tests are not very helpful for genealogical purposes, I'd like to point out a few important exceptions: a.. First, you might be lucky enough to have rare mtDNA (taking the tree analogy a little further, you could think of this as coming from a branch or even a twig with very few leaves on it). This was true of Ann Turner, who co-authored Trace Your Roots with DNA: Using Genetic Tests to Explore Your Family Tree with me. Some people like Ann have very few, if any, mtDNA matches. Even though she is also in haplogroup H, the most common European one, she has a couple of additional mutations that reduce the number of exact matches all the way down to one. In cases like this, it makes sense to play the matchmaking game and compare notes. b.. Second, you might be dealing with degraded remains, as is often the case with history mysteries. For instance, I recently worked on a BBC show to try to identify the two skeletons found in the turret of the USS Monitor a few years ago. In cases like this, scientists would love to use Y-DNA, but it's too fragile and doesn't survive. MtDNA, by contrast, is plentiful, so it is more resilient. It's not as precise, but it's usually all scientists have to work with. So in this case, I took the maternal lines of the sailors who lost their lives in the USS Monitor, and traced them forward in time to find living maternal relatives to serve as a basis for comparison to the DNA extracted from the remains. This is also what I routinely do on my cases for the U.S. Army's repatriation project (to help identify remains of servicemen still unaccounted for from WWII, Korea, and Southeast Asia). c.. Third, you may have a specific, maternally-oriented genealogical conundrum--and if you're strategic about it, you just might be able to come up with a clever way to resolve it using mtDNA testing. Theere are a few examples on pages 69-73 of "Trace Your Roots with DNA." (Those who are registered at Amazon can use the "search inside this book" feature to view these pages or you can click here for a detailed version of one of the examples given). ...A Couple of Caveats To this list of exceptions, I now need to add a pair of qualifiers. The good news is that testing companies and avid genetealogists are working together in an attempt to refine haplogroups. For instance, when I first got my mtDNA tested several years ago, I learned that I was H. Now I can find out that I'm H1*. Returning to the tree analogy, it's somewhat akin to learning which twig off of the H branch my maternal line comes from. Also, mtDNA is finite. It has 16,569 base pairs, which sounds like a lot, but is nothing compared to the billions of bases found in nuclear DNA that's used for Y-DNA tests. So it's in the realm of the possible to test for your entire mtDNA sequence, which translates into very precise results. The catch? Well, there are two. Once you have your sequence, you can theoretically play the matchmaking game again, but at prices currently in the $795-895 range, you probably won't have too many to compare against until prices come down. And I need to point out that a full-sequence mtDNA test is the first genealogical one that could conceivably give away medical secrets. Some conditions are passed through maternal lines (e.g., some kinds of muscle disorders), so your results could potentially reveal more than you'd care to know. Of course, you'd have to take your results (which are well-protected) and do some fairly intensive research or consult a genetic counselor, but in the interest of full disclosure, I feel obligated to mention this possibility. Hop in the mtDNA Pool! If you're new to genetic genealogy, I know this is a lot to absorb, so I'd suggest that you start with more conventional Y-DNA testing, perhaps joining a surname project. But if you're ready to take the next step or are just plain curious, I hope this primer will help you understand just what you can and can't learn from mtDNA testing. About the Author Megan Smolenyak Smolenyak, co-author (with Ann Turner) of Trace Your Roots with DNA: Using Genetic Tests to Explore Your Family Tree (as well as In Search of Our Ancestors, Honoring Our Ancestors and They Came to America), can be contacted through her websites Genetealogy.com, Honoring Our Ancestors, and Megan's RootsWorld. Upcoming Appearances by Megan a.. 02 September 2006, Boston, Massachusetts Joint Genealogical Speakers Guild and International Society of Family History Writers and Editors luncheon at the FGS conference b.. 21 October 2006, Ramapo, N.J. David Ackerman Descendants 1662 c.. 11-18 November 2006, Mexican Riviera 2006 Genealogy Conference and Cruise, hosted by Wholly Genes Software d.. e.. Terms & Conditions | Privacy Statement | About Us | Partner with Us | Contact Us Copyright 2000, MyFamily.com. This article may be reproduced in whole or in part for non-commercial purposes provided that proper attribution (including author name) and copyright notices are included