Tuesday, 30 May 2017

Using Ancestry's Surname Filter

I decided to utilise the surname filter tool on my Ancestry DNA matches to try and determine which ancestral lines some of the 2500 matches might be on.  It should be noted that the filters will only identify other DNA test subjects, where the person tested has also created a family tree on Ancestry - if a person has not created an ancestral family tree on Ancestry, then they will not show up when you filter by surname.  When you enter a surname into the filter field, the quantity of matches will be limited to show only the DNA test subjects who have that surname in their ancestral family tree.
My Great Great Grandmother, Elizabeth Hemblen was transported to Tasmania in the 1850s for stealing a frying pan, and although we have strong circumstantial evidence that "our" Elizabeth was the daughter of a Stonemason in Bath, Somerset, named Isaac Hemblen, we don't have any firm evidence, so a DNA match with other descendants of Isaac Hemblen, would add more credibility to the paper research to date.
When I filtered my 2500 Ancestry DNA matches with the surname Hemblen, I had only one match - Diane R.  So far so good!
Hemblen Filtered Matches
 Investigating further, I found that Diane and I are predicted to be 5th - 8th cousins, and that we share 6.4 cM (centiMorgans) of DNA on a single segment of one chromosome. 
Shared DNA Details
This is the point, when looking at DNA matches on other DNA testing websites, that I would look at the details of how many cM we shared, on which chromosomes, and compare the matching segments to other known matches, to try and isolate which ancestral line the match is likely on.  Unfortunately, with Ancestry, this is as good as it gets.
But, again using the Ancestry surname filter, I tried various surnames, to see which other surnames also appear in Diane's ancestry.  The first surname that I tried was Meale, the surname of Elizabeth Hemblen's husband (my great great grandfather) - Diane R. was not in the list of matches.  Next I tried surnames associated with spouses of Elizabeth Hemblen's siblings and half siblings.  Diane R. appeared as a match when I filtered with the surname Stainer, suggesting that Diane is a descendant of Elizabeth's half-sister, Jane Hemblen, who married William Stainer.  By filtering with the surname Enefer, I was able to narrow down the potential match to Thomas Coffin Stainer, son of Jane Hemblen, who married Mary Ann Enefer, suggesting that Diane is a descendant of Thomas Stainer and Mary Ann Enefer.
I contacted Diane, and outlined how I believed we are connected, and within 24 hours she confirmed that Thomas Stainer and Mary Ann Enefer were her great grandparents.  Diane and I are actually 4th cousins, a little closer than Ancestry suggested.
So despite the limited information provided by Ancestry on which segments of which chromosomes I share with Diane, the Ancestry surname filtering tool provided a high level of confidence in identifying how we connected, and I now have much greater confidence that Elizabeth Hemblen, daughter of Isaac Hemblen is my great great grandmother.

Wednesday, 3 May 2017

Pet Peeves with DNA Matching

With the exception of those who test with 23andMe for health related information, the vast majority of people take autosomal DNA tests to identify familial connections.   But many people severely limit their opportunities to identify connections with others by not maximising the functionality of the testing service. 

My pet peeves related to DNA testing for family history are -
  1. People who do not reply to messages related to a DNA match - Communication with others who share portions of your DNA is the best way to establish how you may be related, or to get help with achieving your objectives of taking a DNA test.  If someone contacts you, have the courtesy to reply.
  2. No associated family tree - All of the major testing companies (and GEDmatch) provide a facility for publicising your ancestral family tree, and all provide protections for hiding information on living people.  Publish the information that you know, to make it easier for DNA matches to see how you might be related.
  3. Associated family tree is not public - Why hide your research from others?  You may have identified an ancestor that others have not, or you may have made a mistake in identifying an ancestor.  If your online tree is private, you will miss the opportunity to help others and correct errors.
  4. Anonymous people on 23andMe - I am still on "the old experience" so I get to see that I have a DNA match, and how much DNA we share, but I cannot contact people who have chosen to be anonymous.  Why did they bother taking the test?
  5. DNA result not uploaded to GEDmatch - If you have tested with one of the major DNA testing companies, you can avoid a lot of the drawbacks of the individual companies' capabilities by uploading your DNA test result to GEDmatch, which facilitates matching between people who tested with different companies.
  6. Not accepting genome sharing requests on 23andMe - 23andMe (the old experience) does not automatically show you which segments of which chromosome you share with another customer, so you have to send a genome sharing request to each potential match, to identify which segments you have in common.  If you do not accept genome sharing requests you can only identify that you share DNA with a person, but have no idea of which line you may be related on.
  7. Ancestry and MyHeritage do not provide information on which segments of which chromosomes are shared - These two testing companies know exactly which segments of which chromosomes you share with every other person in their database, but they choose to not provide you with the information.  At least 23andMe lets the user decide to share or not share, but Ancestry and MyHeritage severely limit their DNA test capability by not allowing users to ever see this information.
Please, take a few minutes to -
  1. Check the privacy settings on your DNA test account
  2. Upload a GEDCOM file of your ancestors or manually add your ancestors to the family tree associated with your DNA test account, and make sure that viewing the tree is not restricted
  3. Upload your DNA test results to GEDmatch, and include a GEDCOM file
  4. Check for new matches every week or two
  5. Communicate, communicate, communicate!