Tuesday, July 6, 2010

New Tool Coming to 23andMe: Ancestry Finder

This weekend, I had the opportunity with several others to beta test a new feature from 23andMe. It is called Ancestry Finder. Although it is billed to help you find ancestral countries of origin, it may or may not be able to deliver on that promise.

For most individuals this will not be possible from the data that is presented; however, I find it very helpful especially with the lack of participation of others on 23andMe when asked to share genomes. This feature may help fill in holes there.

The data is self reported by 23andMe participants who have finished the survey, "Where are you from?"  This survey asks about the participants' grandparents and the data is used to determine the ancestral countries of the person whose match will show. Persons who do not finish the survey will not have their shares seen by others. 

Here are some of the highlights and some screen shots of the feature. Click on any of the images for larger versions that will be clearer.

The following image shows my shares with the default settings of 10cM of shared DNA segments, with the matches only with four grandparents from one country, and all colonial matches (USA, Canada, Australia, New Zealand, and South Africa) turned off.  I only have two matches that fit all three of the default criteria.  In this shot, I have placed my mouse over the segment on chromosome 10.  I am sharing 11.7cM (centimorgans) with a person whose four grandparents were born in Germany.

In this second image, still with the defaults set, I have placed my mouse on the share on chromosome five.  This individual's four grand parents were born in Poland and I am sharing 15.3cM - which puts me at sharing about .20% of my DNA with this person and places us in a possible fourth cousin relationship.  This is interesting as I have no known Polish ancestry; however, it may be an ethnic German who remained in what was part of East Prussia that was ceded to Poland. 

Since I am managing my profile, as well as the profiles of my two brothers, here are our results.  The settings are wide open with shares as low as 5cM, the grandparents can be from different countries, and colonial countries are represented.

Brother Number One

Brother Number Two

My Genome Shares

The above three graphics indicate what DNA my brothers and I share with the same and different people.  Of the people we share DNA with, about 42% of these individuals are unique to one of us and do not share genomes with the other two.  To illustrate this, here is an enlarged version of the shares on chromosome 2. Notice the similarities and the differences.

This is a manipulated image and you will not see this in Ancestry Finder.

Here are my list of countries that match the above graphic. The countries represent places where the grandparents of the 23andMe participants (who match my DNA) were born.  This is not to be construed as my ethnic background; however, it could indicate some nationalities I may have of which I was previously unaware.

Note: there are 26 countries represented.  Of these, I only have claimed 8 as ancestral lands or countries where known cousins have lived.  I will be interested in seeing how these other countries are connected to my family.

One of the features in Ancestry Finder is the ability to place your mouse over a country's name and see only the matches that match that particular location. Since I have no Italian ancestry to my knowledge, I picked Italy.

There are 9 segments representing Italy.  Four subjects had one grandparent born in Italy, while the remaining five had two grandparents who were born in that country. My ancestors had crossed into Italy and lived close to the Franco-Italian border during the 1600s.  It is possible that some of these individuals are descended from that particular ancestral line.

As you can see, there is much to explore in Ancestry Finder.  I am excited about the forthcoming tool and the opportunity to review it. In that spirit, here is my analysis of the ups and downs of Ancestry Finder. It won't be for everyone, but I see much value in using it. Here are the positives vs. the negatives.


  1. It gives you a graphical representation of where matches are occurring on chromosomes.
  2. It shows matches of people who have filled out the “Where are you from?” survey – who may not be showing on Relative Finder (for a variety of reasons).
  3. By comparing segment lengths, it may (or may not) give some clues to the ancestry of a non-responsive person on Relative Finder – such as that elusive 3rd cousin with a .90% match who will not respond to your requests to share and you have used up your three Relative Finder contacts. You may be able to at least assign the match to a particular line (i.e., if your maternal grandmother was French and your other grandparents were English and the match has all grandparents as being French born – there is an indication that the relationship probably (not absolutely) comes from your maternal grandmother’s line).
  4. The threshold can be dropped to 5cM. The threshold on Relative Finder is 7cM. 5cM shares only show when contacted directly outside of Relative Finder.
  5. It can be adjusted so that only individuals with 1, 2, 3, or 4 grandparents from the same country can be returned (1 gives you everyone).
  6. The settings can be adjusted so the minimum threshold can be as set between 5cM and 15cM.
  7. The country of birth is identified for each of the person’s specific grandparents (when known).
  8. A filter can be applied to eliminate seeing those with grandparents born in colonial countries (US, Canada, Australia, NZ, & South Africa). This is actually the default setting.
  9. Segment sizes are exact and not rounded as is Family Inheritance Advanced.
  10. It allows you to see various profiles under an account without physically switching to that profile.
  11. There is anonymity for those not wanting any contact from other researchers.
  12. The survey allows for ethnicity data to be entered (not currently used, but may later be used).
  13. Haplogroup information is missing from Ancestry Finder – this is good thing as too many people are confused by haplogroups on Relative Finder anyway.
  14. A preselected list of countries reduces human error and forces survey participants to pick the current country name.
  15. It is very easy to use.
  16. A mouseover the list of country names shows only those returns where a grandparent’s nativity is shown.
  17. This is a nice extra that I was not expecting to get when I signed up for 23andMe. Thanks guys/gals.


  1. Grandparent nativity may not shed any light on a relationship as it is too general of a measure.
  2. Grandparent nativity does not speak to specific nationalities or ethnicities.
  3. Self reported data on grandparent nativity may be incorrect due to a mistake or lack of correct knowledge of the survey respondent.
  4. Produces a false sense of nationality when a person assumes that an ethnicity is present in his or her own line when a match has four grandparents born in a particular country. Just being born in a country does not constitute a particular ethnicity only nativity.
  5. Not everyone on Relative Finder is represented – only those who finished the survey.
  6. The survey cannot be changed and mistakes cannot be corrected.
  7. The Flash based graphics are hard to see where there are overlaps of individuals matching.
  8. Currently, the ethnicity information in the survey is not being returned.
  9. Haplogroup information is missing from the returns – making identification with non-sharing Relative Finder cousins more difficult.
  10. Some colors representing countries are similar to others (or even the same) and may or may not cause some confusion. I doubt if this could be corrected as shades of colors often look the same on certain browsers. This is really not that big of a deal.
  11. A preselected list of countries does not take into account historic borders or former country names (this is good for efficiency, but perhaps bad for genealogists). I wouldn’t suggest doing it any differently.
  12. Mouseovers may be difficult (not impossible) to perform on contiguous segments.
  13. Genome segment starts and ends are not provided.
  14. The minimum threshold can only be set to a high of 15cM – may not be enough for those having 1000 matches.
  15. The size of the Flash interface cannot be increased or decreased by using CTRL+ or CTRL- therefore, it may be difficult to see some of the shares on a busy chromosome in some higher screen resolutions.
  16. The listing arrangement of grandparents is backwards from how genealogists spatially arrange trees and relationships. Currently, Ancestry Finder lists the grandparents in the following order: Mom's mother, Mom's father, Dad's mother, and Dad's father. Typically, the male lineage is on the left as Dad's father, Dad's mother, Mom's father, and Mom's mother.
  17. It won't meet everyone's specific needs.

It is an exciting time at 23andMe and their discussion area was burning up this weekend regarding this forthcoming feature. I’d like to thank the powers that be for considering me to be a beta tester on this new tool that can be added to a genetic genealogist’s arsenal of weapons.