I just published a blogpost about endogamy - shared DNA at http://segmentology.org/2015/12/02/endogamy-i/ The bottom line is that endogamy only affects the shared DNA when you and/or your Match have your Common Ancestor in you Tree(s) more than once. For each time the Common Ancestor is repeated in a Tree, the nominal shared DNA is multiplied by that factor: E3 is 3 CAs in a Tree and the nominal total shared DNA will be multiplied by 3. In general endogamy does not increase the size of shared segments, just the total amount. In general, we don't have close endogamy, it's usually back in our ancestry somewhere. The multiplying effect of endogamy is offset by the small amounts of shared DNA with distant cousins. However, between endogamy and wide tails on cM distribution curves, we get enough shared DNA so that most of our Matches appear to be in the 6-8th cousinship range. Jim Bartlett www.segmentology.org

In Pakistan, 80% of the population is married to their first cousin. How does that affect their DNA? Sam Sloan On Wed, Dec 2, 2015 at 12:43 PM, Jim Bartlett via < genealogy-dna@rootsweb.com> wrote: > I just published a blogpost about endogamy - shared DNA > at http://segmentology.org/2015/12/02/endogamy-i/ > The bottom line is that endogamy only affects the shared DNA when you > and/or your Match have your Common Ancestor in you Tree(s) more than > once. > For each time the Common Ancestor is repeated in a Tree, the nominal > shared DNA is multiplied by that factor: E3 is 3 CAs in a Tree and the > nominal total shared DNA will be multiplied by 3. > In general endogamy does not increase the size of shared segments, just > the total amount. > In general, we don't have close endogamy, it's usually back in our > ancestry somewhere. The multiplying effect of endogamy is offset by the > small amounts of shared DNA with distant cousins. > However, between endogamy and wide tails on cM distribution curves, we > get enough shared DNA so that most of our Matches appear to be in the > 6-8th cousinship range. > > > Jim Bartlett www.segmentology.org > > ------------------------------- > To unsubscribe from the list, please send an email to > GENEALOGY-DNA-request@rootsweb.com with the word 'unsubscribe' without > the quotes in the subject and the body of the message >

One of my projects is an endogamous group in the US in more recent history. My great grandparents were first cousin. In the area where they lived there were only a handful of families and newcomers were discouraged from settling in the area so there was a LOT of intermarriage. I have the same 3d great grandfather in my tree three times and another one twice. I have cousins from this area who are 4th cousins but appear to be 2d cousins, however, even this cannot be generalized in the numbers due to the randomness of inheritance as I have some others who are also multiple cousins (I say multiple as it is beyond double--some are 4th cousins EIGHT AND NINE times)And yes, my mother is my cousin several times too! LOL Anyway bottom line it is as unpredictable as normal inheritance that doesn't include recent kinships such as this. Some share more than you would expect, others are closer to spot on with the predictions. I took an interest in this topic a little over two years ago and was suprised, pleasantly at the number of cousins on that side of the family who were willing to test to see how our kinships played out knowing many of us share the same ancestors more than one in our trees. On Wed, Dec 2, 2015 at 2:43 PM, Jim Bartlett via <genealogy-dna@rootsweb.com > wrote: > I just published a blogpost about endogamy - shared DNA > at http://segmentology.org/2015/12/02/endogamy-i/ > The bottom line is that endogamy only affects the shared DNA when you > and/or your Match have your Common Ancestor in you Tree(s) more than > once. > For each time the Common Ancestor is repeated in a Tree, the nominal > shared DNA is multiplied by that factor: E3 is 3 CAs in a Tree and the > nominal total shared DNA will be multiplied by 3. > In general endogamy does not increase the size of shared segments, just > the total amount. > In general, we don't have close endogamy, it's usually back in our > ancestry somewhere. The multiplying effect of endogamy is offset by the > small amounts of shared DNA with distant cousins. > However, between endogamy and wide tails on cM distribution curves, we > get enough shared DNA so that most of our Matches appear to be in the > 6-8th cousinship range. > > > Jim Bartlett www.segmentology.org > > ------------------------------- > To unsubscribe from the list, please send an email to > GENEALOGY-DNA-request@rootsweb.com with the word 'unsubscribe' without > the quotes in the subject and the body of the message > -- Lisa R Franklin RN,BSN Admin, Franklin Y DNA Project http://trackingyourroots.com/FranklinGenetics/ FranklinGenetics@gmail.com http://trackingyourroots.com/DNA (How To presentation (23andme), tips, & helps. *2**3**&**m**e**: **The World's Largest database & coincidentally the ONLY one with all the tools you need for genealogy and DNA!--* http://refer.23andme.com/v2/share/6158544791499756901/4672616e6b6c696e47656e657469637340676d61696c2e636f6d BEST GENETIC GENEALOGY BOOK! http://www.amazon.com/Genetic-Genealogy-Emily-D-Aulicino-ebook/dp/B00HJJWBU2/ref=sr_1_1?ie=UTF8&qid=1391174801&sr=8-1&keywords=Genetic+Genealogy