17 September 2010

Population Finder from Family Tree DNA

Do you know your ancestry? Are you Irish? Jewish? Japanese? African? Native American? It is possible that you do know, but our ancestors have traveled far and wide to bring us to where we are. You may be totally correct, but then you may be surprised at what you can discover with Family Tree DNA’s new addition to its Family Finder test called Population Finder.

Most of us determine our heritage based upon our knowledge handed down from the family. If our known ancestors lived in Ireland, we must be Irish. That is not always the case. Even those who feel they are totally European may not be. Those who are adopted may not have any idea of their heritage. Our ancestors’ migration has been immense over the last few hundred to a thousand years.

Population Finder compares your autosomal DNA results with populations from around the world and shows you the amount of shared ancestry you have with one to four of those populations. Family Tree DNA uses various populations based upon published scientific studies. This database will naturally grow over time so the information you receive now may vary and become more refined in the future. A list of the current populations and their subgroups can be found in the Population Finder FAQ.

As political boundaries do not determine genetic populations, Population Finder cannot determine in which country your ancestors lived. For example, Sicily was settled by at least twelve different cultures prior to it becoming part of Italy, and as this area was on a major trade route, there were other cultures that passed though, leaving a bit of their DNA among the locals. Anyone testing from that region could show a large variety of autosomal DNA from Africa, the Middle East, Europe, or other locations. Populations are determined to be in locations based on their frequency, and those locations do not have specific country names.

My husband would refer to himself as totally Italian. All four of his grandparents were born in either Italy or Sicily. Of the lines currently known, everyone lived in these areas. His Y-chromosome is R1b, and his mtDNA is HV. Both of these indicate Western Europe. However, remember that only the autosomal result is used for Population Finder and not the Y-DNA or mtDNA.

When viewing his autosomal results in either Population Finder's bar or pie graph option, we discover that he has 28.39% of his DNA matching populations from the Middle East and the rest from Southern Europe. That’s quite a bit from the Middle East for an all-Italian guy!

Interestingly, I have 100% European matches. All my known lines (in many cases back to the 1600s) are from Ireland, Wales, Scotland, England, and Germany. Although a bit boring as a graph, this large percentage indicates that my ancestors lived in these areas for a long time.

Our son Jason has 29.91% from the Middle East and the rest from Europe. (Well, I have made the comment that he is his father’s son!) To explain Jason having a higher percentage from the Middle East than Gary, Rebekah A. Canada, Genetic Genealogist and Graduate Student in Bioinformatics, states that “Southern Europe and Middle Eastern are very close. Some of the ancestry from Gary's Southern European ancestry is being picked up as Middle Eastern in Jason.”

The margin of error in Jason’s calculations is +/-17. 08% whereas Gary’s is +/-8.95% and mine is +/-0.01%. Family Tree DNA indicates that a high margin of error (+/-15%) exists when two populations are very close. This high margin of error indicates that Population Finder is not able to distinguish between two populations with great confidence, and this makes perfect sense as the history of this area is known to draw many diverse populations.

If your result has a high margin of error, you are asked to take the Population Finder Survey. It helps reduce the margin of error in your related populations. If you are uncertain of your ancestral origins, perhaps you are adopted or do not know among a couple of possibilities, you can choose None of the Above.

Gary and Jason fell into the rare 0.4% of participants who needed to take the survey. Rebekah A. Canada indicates Gary and Jason’s margin of errors remained higher because None of the Above was the option chosen since Italian is not a selection as you can see from the survey options below.

Gary's choices:
Middle Eastern
Middle Eastern/North African
None of the above

Jason's choices:
Middle Eastern
None of the above

After the common R1b Western European haplogroup and with the additional resource of Population Finder, I have a genetically exotic husband after all! ...And he has a very ethnically stable wife!

So…how does this help the genealogist?

Any genealogist who faces a brick wall within the most recent five to six generations and whose ancestry is likely to cross ethnic groups can benefit. Adoptees who are uncertain of their ethnic origins can find Population Finder helpful. In my opinion, any resource which provides new clues can be the one that helps us through those brick walls.

Population Finder is currently in Open Beta, meaning that if you have tested with Family Finder, you can experience this feature first hand before the general public.

More additions to Family Finder are being developed, so watch this blog for the latest.

Emily Aulicino
© 17 Sept 2010

1 comment:

  1. Great explanation of the differences between the two companies. I tested my dad using Family Finder first and before all the recent additions. Later tested with 23andme. Your post reminded me to go back and check dad's Family Finder results. Still no matches but did check out the charts. The more DNA testing I do the more I still come back to thinking that FTDNA is still head and shoulders above the bulk of the other testing companies.