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Can a person be 26% indian?

  1. Jun 9, 2017 #1
    Is it possible for a person to be 26% Indian? When I think about genetics, I assume that people must be proportions that have 2,4,8,16,32,etc and a denominator. For example a person whose mother is 1/2 french, 1/2 English and has a father that is 100% German would be 50% German, 25% French and 25% English. I saw a TV commercial that came from Ancestry.com that said a person was 26% Indian. Is this possible? If so, how.
  2. jcsd
  3. Jun 9, 2017 #2
    one parent is 50%, hence you inherent 25% indian from that parent.
    The other parent is eithet 1.56% or 3.12% so you inherit 0.78% or 1.56% respectively.

    For a total of 25.78% or 26.56% either of which ,depending on rounding, could be said to be 26%
  4. Jun 9, 2017 #3
    I figured that rounding must have come into play. is 1.56% and/or 3.12% legit? Are these some fractions with 32,64, 128 as a denominator?
  5. Jun 9, 2017 #4
    1/32= 0.03125 or 3.125%
    1/64=0.015625 or 1.56%
  6. Jun 9, 2017 #5
    Got it. Thanks,
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  7. Jun 9, 2017 #6
    yes, probably. Someone has to pay for the servers I guess!
  8. Jun 9, 2017 #7


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  10. Jun 9, 2017 #9


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    Hmm...is it even possible for someone to be 100% Indian? What would that mean genetically?
  11. Jun 9, 2017 #10


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    If the determination of ancestry is only done by pedigree, then you will be limited to particular numbers depending the various crossed that lead up to the genome in question.
    However, if the measurement was based on a large number of molecular markers, than more refined and accurate percentages of inheritance can be determined.

    This can happen because you could inherit particular chromosomes from a parent or grandparent that resulted from recombination (crossing over) between chromosomes of different ancestral sources (such as German and English). The pedigree approach relies on an average of the inheritance for a particular cross. It assumes recombination would result in something like a 50-50 mix of the parental chromosomes), the molecular approach actually measures how much of each inherited parental chromosome is present in a particular individual. The recombination events can be anywhere along the length of the chromosome, so that when a recombinant chromosome is inherited in later generations, it will bring with it differing amounts of one or the other ancestral chromosomes.

    This approach has been used to speed up or slow down inbreeding in genetic lines. it is used to can save generations of time in the production of inbreed genetic lines.
  12. Jun 9, 2017 #11
    There are no genes which determine a person's nationality and culture.
    A few genes determine what broad ethnic group they probably originate from.
    You could say that a person's ancestors are likely to be mostly Asian, but not a lot more.
    Last edited: Jun 9, 2017
  13. Jun 9, 2017 #12

    Vanadium 50

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    The assumption that you have 2^n distinct ancestors is wrong.
  14. Jun 10, 2017 #13


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    And how many generations back do you have to go before your individual ancestors of that generation are "purebred"?

    My mother's parents immigrated to the US from Finland, so I'm nominally 50% Finnish. However, the farm (still in existence!) that my grandfather was born on is near the part of Finland along the Gulf of Bothnia that was settled by Swedes during the medieval period. Drive 10-20 miles towards the coast and the number of native Swedish-speakers increases dramatically. So how much of that 50% is actually Swedish?
  15. Jun 10, 2017 #14


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  16. Jun 10, 2017 #15
  17. Jun 11, 2017 #16


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