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  • Founder effect and matches

    While waiting for my deep clade test to be completed I have been reading different genectic based articles. While reading it occurred to me I am a part of founding population. I am the first generation of my family to be born in the US. My earliest ancestor goes back to Quebec to at least 1635.
    Here is a blurb from a Canadian Biotech web site:The unique history of the Quebec French-Canadian population makes it among the best founder populations in the world for gene discovery.
    A founder population is a group of people who are all descended from a limited number of common ancestors and who have been isolated from intermarriage with outside groups for several generations by means of culture, religion, language, geography or some other factor.

    Could this account for why I have no matches here,ysearch,ancestory or any other place?

  • #2
    Interesting, but almost the exact opposite of what I expected.

    The founder effect is more often the explanation for an extraordinarily LARGE number of matches. Basically what they're saying here is that due to some historical bottleneck conditions, a genotype becomes atypically common--at least within a given locality.

    But at the end of the day what we're dealing with is sampling risk--the risk that the people who've tested and shared their results to date are NOT reflective of the frequency of a genotype in the population as a whole.

    It's impossible, really, to say whether you have such few matches because your genotype actually and truly rare in the population or whether by dumb (bad) luck that very few matching people have tested yet. There's all kinds of complicated statistical formula that could theoretically be applied to get a reasonable estimate of your confidence that the population tested to date fairly represents the whole population, but the amount of information required is probably impractically enormous. My own personal guess is that nowhere near enough people have tested to date.

    One thing for certain, your lack of matches is NOT consistent with the founder effect and a pedigree going back to early Quebec.

    Don't feel too bad. I'm more of less in the same boat. Six years on and no information worth writing home about either. Probably just dumb luck. Could change later today or never. Just the nature of luck, I guess.



    Originally posted by Brunetmj View Post
    While waiting for my deep clade test to be completed I have been reading different genectic based articles. While reading it occurred to me I am a part of founding population. I am the first generation of my family to be born in the US. My earliest ancestor goes back to Quebec to at least 1635.
    Here is a blurb from a Canadian Biotech web site:The unique history of the Quebec French-Canadian population makes it among the best founder populations in the world for gene discovery.
    A founder population is a group of people who are all descended from a limited number of common ancestors and who have been isolated from intermarriage with outside groups for several generations by means of culture, religion, language, geography or some other factor.

    Could this account for why I have no matches here,ysearch,ancestory or any other place?

    Comment


    • #3
      Originally posted by Brunetmj View Post
      Could this account for why I have no matches here,ysearch,ancestory or any other place?
      All the people I know with New France ancestry have many autosomal matches, most of them with people actually from Quebec or with Franco-American ancestry. I guess you are talking about yDNA, though, and it's possible nobody else in your line happens to have tested yet, France is very undertested.

      Comment


      • #4
        The explantion of founding effect I saw read something like
        "As a result of the loss of genetic variation,the new population may be distictively different; both genetically and phenotypically from the parent poulation from which it is derived. In extreme cases,the founder effect is thought to lead to the speciation and subsequent evolution of new species."

        Now of course I would assume that process to the fullest would take thousands of years. But i also assume a few hundred years could produce some changes from the parent (France) to the YDna (some of the values)
        Naturally I would have no idea what the data base is here that represents
        the french from Quebec who would have been isolated somewhat from the surrounding poulation.

        p.s. my autosomal DNA (not from this site) comes back native american and Russian (Komi) - no clue of what to make of that..I am R1b1a2 and H (mtDna)
        on this site.

        But likely your right. it's just bad luck and combined with few people tested. it was just a theory.

        Comment


        • #5
          The statement you mention seems to refer primarily to the autosomal DNA. 400 year is certainly not enough to generate significant mutations in the Y-DNA. 12/12 matches could go back literally thousands of years. So even if there is no exact match, one should be able to find near matches if the relevant populations are well covered.

          But, as others were saying, the number of matches depends on who has tested. France is vastly undertested (as is Italy). And I don't think Quebec is much tested either. I actually have no matches either, close or distant.

          I suppose that if you had been instead from a founder population like pilgrims or early Virginians, you'd have had dozens, if not hundreds, of matches.

          cacio

          Comment


          • #6
            Interesting thread.

            It got me thinking: Half my ancestry is Slovenian. Definitely a population (small, homogenous, geographically isolated) where there could well be a founder effect.

            Did some research and learned that's the case. They have recently uncovered one of the hereditary breast cancer mutations (BRCA) in Slovenians.

            I, too, have few matches on the maternal/ Slovenian side. Only 3 mtDNA matches; one is Slovenian. My 15 FF matches are all distant cousins and all seem to be through the paternal/Scottish side.

            I agree with the previous posts. Having few matches isn't a necessary consequence of being part of a founder population. It's a function of how many people have tested. (Not too many Slovenians, unfortunately!)

            Blair
            Last edited by bkilpatrick; 24 March 2011, 12:18 AM.

            Comment


            • #7
              It's a function of how many people have tested. (Not too many Slovenians, unfortunately!)
              The more I think about it the more I realize that countries like the US with a high population of immigrants and relative wealth would engage in genetic testing.
              After all a person say from Slovenia would likely know already were their ancestors came from.
              The same is true for France, Italy and most other countries.It is also expensive 200 being just about minimal. Why would anyone pay that for something they already know? So I would think that most people in the database are from countries like the US or have been the subject of medical or scientific testing.

              Comment


              • #8
                Originally posted by Brunetmj View Post
                The more I think about it the more I realize that countries like the US with a high population of immigrants and relative wealth would engage in genetic testing.
                Agreed.
                After all a person say from Slovenia would likely know already were their ancestors came from. The same is true for France, Italy and most other countries.
                Agree, but...
                A person from Slovenia would still like to find relatives in the US.
                It is also expensive 200 being just about minimal.
                I think this is reason number one. It is still very expensive and many can't afford several hundred dollars even if they really want a DNA test.

                Comment


                • #9
                  Originally posted by k.o.gran View Post
                  Agreed.

                  Agree, but...
                  A person from Slovenia would still like to find relatives in the US.
                  Hmm, I wonder. I don't have the sense that present day Slovenians are so fascinated by their distant American cousins that they are searching for us

                  Good question, though. In European countries where there could be more of a population mix, is there much interest in personal DNA testing?

                  Comment


                  • #10
                    Originally posted by bkilpatrick View Post
                    Hmm, I wonder. I don't have the sense that present day Slovenians are so fascinated by their distant American cousins that they are searching for us

                    Good question, though. In European countries where there could be more of a population mix, is there much interest in personal DNA testing?
                    I can obviously only speak for myself, but finding relatives in the US was one of the reasons I took the test. I'm a Norwegian.

                    Comment


                    • #11
                      Originally posted by k.o.gran View Post
                      I can obviously only speak for myself, but finding relatives in the US was one of the reasons I took the test. I'm a Norwegian.
                      I would love to have someone in Slovenia coming searching for me So far it's only been the other way around.

                      Comment


                      • #12
                        Originally posted by bkilpatrick View Post
                        I would love to have someone in Slovenia coming searching for me So far it's only been the other way around.
                        Yes, we all dream of the fantastic Ukranian blonde showing up to our doorsteps . . . .



                        But on a note more tangentally related to genealogy, that kind of did happen to my old man some years back. Got a letter from a hospital claiming to care for a 1/2 brother he'd never even heard of, and who'd in fact been born 10 years before himself . . . a letter asking for money to support his care.

                        My old man was outraged and offended, and told the hospital in so many words, rather burning any bridges that may have been there. Or so I am told--this was many years before I was even born.

                        Turns out, however, there was at least a grain of truth to the story. I verified later through independent inquiries that my father did indeed have a mentally disabled 1/2 brother of that name who lived for a very long time in a hospital in that state.

                        Of course, I don't know whether those types of requests are considered legally kosher, or whether all the paperwork was in order at that time and had been presented to my father--or that it even would have mattered. My grandfather had died very shortly after my father's birth, so my father grew up his whole life thinking of the existence of family as some kind of hypothetical abstraction that might look sensible on paper but just didn't jive with actual lived experience. It was only natural that he saw this as some type of come on.

                        Comment


                        • #13
                          my father did indeed have a mentally disabled 1/2 brother of that name who lived for a very long time in a hospital in that state.
                          Kind of interesting that this should come up in a thread I started. I actually work with people with what we now refer to as people with developmental disabilities. At one time people were encouraged just to leave them and don't contact them anymore. Of course today we encourage full family participation.

                          But let's get back to the ukrainian blonde

                          Comment


                          • #14
                            Originally posted by Frederator View Post
                            Yes, we all dream of the fantastic Ukranian blonde showing up to our doorsteps . . . .



                            But on a note more tangentally related to genealogy, that kind of did happen to my old man some years back. Got a letter from a hospital claiming to care for a 1/2 brother he'd never even heard of, and who'd in fact been born 10 years before himself . . . a letter asking for money to support his care.

                            My old man was outraged and offended, and told the hospital in so many words, rather burning any bridges that may have been there. Or so I am told--this was many years before I was even born.

                            Turns out, however, there was at least a grain of truth to the story. I verified later through independent inquiries that my father did indeed have a mentally disabled 1/2 brother of that name who lived for a very long time in a hospital in that state.

                            Of course, I don't know whether those types of requests are considered legally kosher, or whether all the paperwork was in order at that time and had been presented to my father--or that it even would have mattered. My grandfather had died very shortly after my father's birth, so my father grew up his whole life thinking of the existence of family as some kind of hypothetical abstraction that might look sensible on paper but just didn't jive with actual lived experience. It was only natural that he saw this as some type of come on.
                            Re: the fantastic Ukrainian blond showing up: I'd prefer a dark a dashing Slovenian poet! But I'm not sure my husband would be too happy.
                            I'm female

                            Re: hidden disabled relatives: There's a fantastic book called Annie's Ghosts, came out in 2009, by Steven Luxenberg, a Washington Post editor. Heard a story just before his mom died about a secret disabled sister, hidden away. Didn't believe it till he got a bill from the cemetery for the upkeep of her grave! He unraveled a family mystery and also discovered the fascinating world of genealogy research.

                            Comment


                            • #15
                              Originally posted by bkilpatrick View Post
                              Re: hidden disabled relatives: There's a fantastic book called Annie's Ghosts, came out in 2009, by Steven Luxenberg, a Washington Post editor. Heard a story just before his mom died about a secret disabled sister, hidden away. Didn't believe it till he got a bill from the cemetery for the upkeep of her grave! He unraveled a family mystery and also discovered the fascinating world of genealogy research.
                              I'm actually reading that. I recently got information on a relative who was in a local asylum, with what seems to have been schizophrenia, through a Freedom of Information request.

                              Comment

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