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    Dna 101

    Hi all, I've been considering getting a DNA (genealogy specific) analysis for curiosity sake for one and hopefully make some connections in my family tree too. I have done some reading on it but I would like to get the Reunion Community to help me decide.

    1) Is there any reason to choose one provider over another?
    2) I assume the accuracy gets better with the larger database, is there a preferred one amongst the community?
    3) How does the matching work, if I choose to get it done do I automatically obtain a list of potential candidates?
    4) I'm curious of my ancestry but my wife not so much, if my children gets a DNA analysis done also would that presumably fill in the gaps on my wife's ancestry? I do have her paternal ancestry (and mine) going back to the late 1600's, certainly it doesn't include the whole picture.

    There are many questions I have, hopefully the responses to these will steer me in the right direction!

    Thanks to all who may reply,
    Hayward
    Hayward...
    Mac Studio, A1 Max, 64GB memory, Sonoma 14.2.1

    #2
    Re: Dna 101

    Originally posted by HJKeats View Post
    Hi all, I've been considering getting a DNA (genealogy specific) analysis for curiosity sake for one and hopefully make some connections in my family tree too. I have done some reading on it but I would like to get the Reunion Community to help me decide.

    1) Is there any reason to choose one provider over another?
    2) I assume the accuracy gets better with the larger database, is there a preferred one amongst the community?
    3) How does the matching work, if I choose to get it done do I automatically obtain a list of potential candidates?
    4) I'm curious of my ancestry but my wife not so much, if my children gets a DNA analysis done also would that presumably fill in the gaps on my wife's ancestry? I do have her paternal ancestry (and mine) going back to the late 1600's, certainly it doesn't include the whole picture.

    There are many questions I have, hopefully the responses to these will steer me in the right direction!

    Thanks to all who may reply,
    Hayward
    As far as providers go, Ancestry has the largest database, by far, while FamilyTreeDNA offers the widest array of tests. Some providers allow you to upload your raw data from competitors, too.

    What I usually do is test with FTDNA and then upload the raw data to Gedmatch and MyHeritage. I like the fact that FTDNA offers male (YDNA) and female (mtDNA) line tests.

    They all seem to follow a similar pattern: they give you a list of matches from their database and allow you to contact them.

    Also, having tested a number of family members (including my parents and two of my children) I recommend you test older people first as the autosomal matches get diluted as you go down a generation. If you have to convince older family members, however, arm yourself with patience as some people are extremely paranoid about such tests.

    Oh, and a final warning: it can get expensive real fast, especially once you get into YDNA and mtDNA tests (it does open up a whole new aspect of genealogy research, however).

    P.S. Keep in mind that this isn't magical: DNA tests can give you hints/leads but will never tell you exactly where that person fits in your family. It can help you validate/invalidate theories, however. Sometimes it will raise more questions than it answers...
    Last edited by bbousquet; 31 August 2018, 11:49 AM.
    Benoit Bousquet
    Reunion 14

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      #3
      Re: Dna 101

      Originally posted by HJKeats View Post

      1) Is there any reason to choose one provider over another?
      2) I assume the accuracy gets better with the larger database, is there a preferred one amongst the community?
      3) How does the matching work, if I choose to get it done do I automatically obtain a list of potential candidates?
      4) I'm curious of my ancestry but my wife not so much, if my children gets a DNA analysis done also would that presumably fill in the gaps on my wife's ancestry? I do have her paternal ancestry (and mine) going back to the late 1600's, certainly it doesn't include the whole picture.
      1) If you really want to get into this you'll eventually want to test yourself at all the companies. Ancestry has a much larger database than the others (I have 10x the matches at Ancestry as anywhere else) and does automatic tree comparisons, so that one is top of my list. MyHeritage is growing fast and has people in Europe who tested and some very nice tree matching. 23andMe has a large database with some good tools (and the ability to see your matches' matches) but most of their customers don't opt into matching - they just want the medical reports or the ethnicity ones. FamilyTreeDNA has the smallest database (of autosomal matches) but has some of the best tools. I would recommend you wait for a sale (Black Friday or the Christmas sales at this point) and then test at Ancestry first. Then you can download your raw test data and upload it to MyHeritage, FamilyTreeDNA, and GEDMatch (which is a free 3rd party way to compare your data across people who tested at other companies). Then buy a test at 23andMe eventually. There is also LivingDNA but it is mostly focused on British at the moment and does not yet do matching. You can load your raw data to LivingDNA for free at the moment - altho you will only get cousin matches - no ethnicity report.

      2) They are all about as accurate as any other. But you will get more matches at the bigger companies. I have over a dozen 2nd and 3rd cousins at Ancestry. I have 2 at FamilyTreeDNA and one at MyHeritage and none at 23andMe. My wife has 40,000 matches at Ancestry, about 4,000 at Family Tree DNA, about 3,000 at 23andMe and a couple thousand(?) at MyHeritage. It's all in the advertising w/re to whether someone chooses to test at one company or another of course.

      3) Yes. Every company provides a list of people in their database who match your DNA and a suggested relationship level (eg. 3rd cousin) Many will also tell you what matches someone has that you also have. Some provide email addresses for your matches, others make you use their internal messaging system.

      4) Each of your children gets a random 50% of your DNA and a random 50% of your wife's. Each child has about 50% DNA that is the same as one of their siblings (and 50% that isn't the same). So, yes, the children will get a good potion of your wife's DNA. However, three siblings will not get all her DNA - more like 85% or so (I haven't done the math recently). I believe it takes 5 or more siblings to get CLOSE to 100% of the parent.

      If you are on FaceBook (or even if you aren't!) you might want to join one of the many genetic genealogy groups there. You can get really good advice. Try DNA Newbie and Genetic Genealogy Tips and Techniques for starters.

      Don

      EDIT: what I said above mostly applies to autosomal DNA tests (such as what Ancestry provides). If you want to consider a Y-DNA test for yourself (which tests your male line up the surname path) or if you want mtDNA (which traces your mother-to-mother-to-mother... line) then Family Tree DNA is the only company that offers those. I have used all three types of DNA tests for my genealogy and found them all invaluable. However, they work very differently and are best in different circumstances.

      Also, you may want to check if your local genealogical society has a DNA Special Interest Group. That can be a VERY good way to get face-to-face help with getting advice and getting started.
      Last edited by donworth; 31 August 2018, 01:28 PM.

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        #4
        Re: Dna 101

        I've given some basic DNA presentations at societies in my region, and confirm most of what the other replies have said, with some additional comments here:

        1) Ancestry has the biggest pool of people who have tested by far, but working with their results is truly productive only if you already have an ongoing subscription with Ancestry. If you do not, and you only take their test, the features available to you are very limited. You can google to find an Ancestry.com page "AncestryDNA with and without a subscription" to see a chart of the differences in capability.

        2) If you do already have an Ancestry subscription, then do start with them. When your results come in, and after doing the process of working with the match list you get from them, then download your results and upload them to MyHeritage (free to do so at this point in time) and to FTDNA (where you pay $19 to unlock full capability and it's worth it, but more work is required to learn how to use a chromosome browser).

        3) GEDmatch (mentioned by a previous reply) comes later and after you understand how to use a chromosome browser and what "triangulation" is. This takes awhile to learn. DO join a DNA Study Group if your local society offers one, or go to DNA sessions at conferences you attend. You could also subscribe to one month of webinars at www.familytreewebinars.com for $9.99 (no long-term commitment) and watch the excellent webinars on DNA they have there, each about 1 hour long plus Q&A.

        4) Ancestry, FTDNA and MyHeritage all have the capability to show you Shared Matches. How this works: you choose one person in your original list of DNA Matches. From there, you choose "Shared Matches" (at FTDNA this is called In Common With). You then get a list of people who are matches to both YOU and they are also a match to the person you chose at the beginning of the process.

        5) Y-DNA testing for the male surname line is great for tracing a male direct surname line. A woman's direct maternal line (her mother, her mother, her mother, etc.) is traced with the mtDNA test, which is expensive because it's only worth doing if you do the Full Sequence ($199 regularly, sales $169). It is very difficult to get results that you can use to find anything, for reasons too complicated to explain here. I'm intrigued to see Don say he found mtDNA testing "invaluable" because I discourage people from doing it unless they have money to burn, i.e. won't be disappointed if can't get results from it.

        Hope this helps.
        Susan
        P.S. Forgot to say: I've heard more than once that 23andMe is not that useful for genealogists because the bulk of people who test there are doing it for health/medical reasons, not because they care about genealogy. This means that far fewer of their testers (your potential matches) have a family tree attached to their results, and few of them will reply to your email when you contact them. It is also true that Ancestry has millions of testers who only wanted to find out if they should be wearing a kilt or wearing lederhosen, and they have not and will never put up a tree or respond to your email. But Ancestry's sheer numbers are so big that it's still worth doing their test if you are already a subscriber.
        Last edited by Susan Freas Rogers; 31 August 2018, 05:55 PM.

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          #5
          Re: Dna 101

          W/re to Ancestry subscription: If you compare what Ancestry gives you without a subscription to what you get at 23andMe, for example, where you can't really create a tree anymore, the subscriptionless option isn't as bad as it looks. And you can still use Library subscriptions to look at matches' trees or you can get them to invite you to their tree. You just don't get the spiffy automated tree matching hints and circles. FTDNA's tree capability is pretty awful (and very difficult to use in my opinion) and they don't really do automated tree comparisons like Ancestry. MyHeritage is much better but you are limited to 250 people in your tree if you don't subscribe. The biggest drawback to Ancestry isn't really the subscription issue, I think, but rather the fact that you can't get to the matching segment data that is available from every other company (aka Chromosome Browser). However, that is somewhat mitigated by using GEDMatch and begging your important matches to transfer their raw data there.

          W/re to mtDNA, the use case for that isn't the same as for atDNA - which is what seems to throw a lot of people. With autosomal (like Ancestry or FTDNA's Family Finder) you just test yourself and then look at all your matches and wait for new people to show up as time goes on. With mtDNA if you do that you aren't likely to get any close matches at all. And if you do get any they will be hundreds of years back to the common ancestor and very difficult to figure out even if they are closer because the surname changes at every generation. So a single mtDNA test isn't all that useful - especially at $200 for a full-sequence test.

          The best way to use mtDNA is the way they used it to prove the woman who claimed to be "Anastasia" was a fake. They sampled some of her tissue, then compared her mtDNA with that of a documented descendant of the Czarina. It didn't match - and if she had been the Czarina's daughter (or even her daughter's daughter's daughter) it should have been an exact match.

          I use mtDNA as pairs of tests. For example, my wife is trying to find the parents of her great-grandmother. My wife just happens to be a matrilineal descendant of her great-grandmother (who is her mother's mother's mother), so we ordered her full-sequence mtDNA test. Then we found a possible couple that could have been the great-grandmother's parents. We researched all the female descendants (daughter to daughter to daughter... ) of that wife's mother. When we found a living matrilineal descendant we begged her to spit in a tube for us. The results did not match my wife's mtDNA at all. So, scratch that couple off - they could not be the parents of my wife's great-grandmother - and now we're researching a different couple, but haven't found a matrilineal descendant to test as yet. When/if we do, if there is an exact match, that will be nearly 100% proof that they are great-grandma's parents. It can get expensive doing this of course - $400 per pair of tests! But, since mtDNA changes very slowly over the generations, it's is far more definitive proof of relationships than atDNA which can get pretty squishy what with the limits of it's reach back through the generations, pedigree collapse, double relationships and IBS segments and the like.

          Don

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            #6
            Re: Dna 101

            I was visiting Prescott, AZ recently and was in the public library where I saw Family Tree Magazine had an article on this subject. In it there were some comparison charts, including one on downloading/uploading your DNA data to each site. GEDMatch is for uploading only as they are not a testing site while Ancestry does not allow uploading of data from the other sites. I took a photo of the uploading/downloading chart:
            Attached Files
            Dennis B. Swaney
            Prescott, AZ

            MacOS 10.13.6; MacOS 12.6; iOS 16; iPadOS 12 & 16

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