13 July 2012

Native American DNA - or Lack thereof in Population Databases

I hope this post doesn't generate a lot of controversy. I can sympathize with Native Americans not wanting to be taken advantage of while also regretting the paucity of Native American DNA in the population databases used to measure ethnicity. Dienekes has an interesting discussion on this in his "Petty identity politics indeed, or, holding a grudge is no excuse for anti-science" post.1

In my DNA presentations I state that testers should not rely too much on the predictions of ethnicity percentages for two main reasons.
  • One, you are only seeing a percentage of how much you match the other populations represented in the database. If your ethnicity isn't represented the percentages will not be accurate. Until we have databases with more samples from all population groups we won't have the full picture.
  • Two, approximately half of the autosomal DNA (atDNA) of any progenitor is lost in each new generation born. It is a roll of the dice as to whether you still have atDNA from any particular ancestor whose ethnicity you are trying to prove. And your percentage of DNA from any particular ancestor can be different from that of your sibling or cousins.

As of today, you can really only use DNA to prove Native American ancestry if it is on your Y-DNA line (passed from father to son and represented by the top line on a left-to-right pedigree chart) or your mitochondrial DNA (mtDNA) line (passed from mother to child and represented by the bottom line on a left-to-right pedigree chart).

pedigree chart


1. Dienekes Pontikos, "Petty identity politics indeed, or, holding a grudge is no excuse for anti-science," Dienekes Anthropology Blog, posted 13 July 2012 (http://dienekes.blogspot.com/ : accessed 13 July 2012).

To cite this blog post:
Debbie Parker Wayne, "Native American DNA - or Lack thereof in Population Databases," Deb's Delvings Blog, posted 13 July 2012 (http://debsdelvings.blogspot.com/ : accessed [date]).

© 2012, Debbie Parker Wayne, CG, All Rights Reserved

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