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Why Y?

Father’s day is always an occasion for the DNA testing companies to offer discounts on their kits and this year is no different. Give Dad a DNA kit is the message. Why should you? Well his autosomal DNA might find cousins you had lost track of, discover ethnicity you were curious about, or solve an unknown parent mystery. After all, he is one generation closer to your ancestors. I tested my late father long ago and am grateful to have that information. Click here for my evaluations of the different autosomal testing companies.

Dad and I in about 1953 (he was in the Air Force)

Only men have a Y chromosome and there are tests for just the Y. Those tests can give you information about your surname and your deep father line ancestry. Family Tree DNA is the place to test just the Y although both LivingDNA and 23andme will give you a high level Y haplogroup, plus there are tools to determine the haplogroup from an AncestryDNA or MyHeritage test (discussed at the end of this post).

If you know what a Y haplogroup is you can skip this paragraph … The 23rd pair of chromosomes is an XX for a woman and an XY for a man. The problem or benefit is that there is no second Y for that Y to recombine with. Thus unlike the other 22 chromosomes a man’s parents give him, the Y is unchanged from his Dad’s and his Dad’s and his Dad’s and so on, except for mutations. Those little changes accumulate over thousands of years and allow scientists to catalog the Y and trace the migration of mankind around the globe. Each set of Y mutations is assigned to a haplogroup, and subgroup, which can tell you where your ancestors came from thousands of years back. Here is the latest diagram from the
wikipedia article on Y

Y haplogroup world expansion – start at the big Y in Africa (A was the first haplogroup) -image from wikipedia by Maulucioni [CC BY 3.0 (https://creativecommons.org/licenses/by/3.0)]

If you are of European origin then click here for the Eupedia articles on each haplogroup.

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Another Unusual DNA Adoptee Case

Janice was searching for her biological father. Her Ancestry DNA test had found what looked to be an aunt or half aunt, “ Sally,” and also a half uncle, “Trevor,” who did not match each other, both about 20 years older than Janice. So likely each of them was related to one parent of the unknown father. This could be easy! But wait…

Display from Ancestry Beta match view: Note that the common ancestor with Sally came after adding her tree

Notice the difference in matching DNA and that they are both listed as 1st-2nd cousins. Yet both are in the range for half aunt/uncle (500-1446 cM). Although other relationships, like first cousin were possible, they did not fit the known facts or the matching to common relatives. Trevor’s second cousins shared with Janice were all showing as third or fourth cousins to her, suggesting one generation of difference. The same was true for Sally’s closer cousins: her firsts were coming up as Janice’s seconds.

Trevor, born 1945, had just discovered via his Ancestry test that the father who had raised him was not his biological dad. His dad was actually his stepfather; he had adopted him when marrying Trevor’s mother. Sadly she was no longer available to tell Trevor who his birth father really was and the father of record did not fit the DNA evidence.

Sally knew that her mother had given birth to a boy in 1944 that had been adopted out. This child was not the son of the man she later married; his father was unknown. Sally had tested her DNA hoping to find her half brother and was excited to have found his daughter!

How Sally and Trevor are related to Janice

The problem here is that since Janice’s father is that adopted half brother, there may be no way to track him down. The best I could do for Janice was to find Trevor’s dad and Janice’s paternal grandfather via DNA. Since he had deep American roots it took less than four hours! That is of my time, but actually a day and a half of elapsed time.

Here is how it was done.
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Time for Jamboree 2019!

The Southern California Genealogical Society puts together my favorite conference every year in Burbank. This year is their 50th anniversary! In my next post I hope to share some of what I have learned here.

However since all the screens on the DNAgedcom client have changed I am too busy updating my presentation on Using DNA for Unknown Parentage Cases,  which will be live streamed tomorrow afternoon, to write a more complete article. Click the image to get to the Jamboree web site and learn more.

 

Please Opt In at GEDmatch

In these modern divisive times, even the genetic genealogy community has been torn into two camps. Is it modern nature to react with emotion rather than thought? With the “are you with us or them”? Is this what overuse of social media has done to us? I can see both sides of the issue. Some of you may wonder what I am even talking about ….

Cece Moore on Dr Phil explaining how she uses DNA to find criminals (click image to go to that site for the article and video)

The problem has arisen because Law Enforcement (LE) has been using DNA and genealogy databases to help find violent criminals and to resolve many old and cold cases like the Golden State Killer (GSK) case. They are using the techniques and tools that were developed for breaking genealogical brick walls and helping adoptees find their biological families. Personally, I applaud this usage and the closure it brings to the families of the victims. A dear 4th cousin of mine lived in fear during her adolescent years in Sacramento because of the GSK.

However the issues of concern for many genealogists are privacy and consent. Frankly, I think you should not test your DNA if privacy is a worry of yours. So many people have tested now that you can be easily identified if you do it too. My son and two nephews have chosen not test for that reason.

How about consent? Consider the site GEDmatch.com, which was developed to let people compare their DNA tests with testers from other companies, as well as provide many helpful additional tools. If you uploaded your DNA there in the past, had you given your consent for this usage? After the GSK case. I marked all the kits I control as research until each person had responded with permission to open it up. Most were happy with the thought that their DNA might out a distant cousin who was a criminal. Polls show that 90% of Americans are OK with this too.

I have been asking everyone again since GEDmatch now has an specific opt in on each kit for LE usage of those test results in comparisons. There is also an opt in for whether the link to your WIKItree compact tree should show. Both are important. Until many more people have opted in, the benefit of the database for LE is very limited.

Why the opt in now? Why is the genetic genealogy community so divided? What happened?
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More Clustering Tools!

There are many new ways to make those beautiful cluster diagrams of how your DNA relatives are related to each other. Both MyHeritage and Gedmatch GENESIS (tier 1) now have clustering tools (Thank you Evert-Jan Blom). These charts give you an easy way to see your family groupings and can help you figure out a new match since each cluster typically represents a common ancestral couple. Click here for my previous posts on clustering which is based on the Leeds method.

My Dads Clusters at Gedmatch GENESIS

The GENESIS cluster diagram shown above includes the total cM each match shares with you as well as their name and kit number. Click on the “i” in a circle for a pop up box with the user information which includes an email address and whether a GEDmatch tree is linked to this kit. Any of the colored boxes on the graph can be clicked to open a window for a one to one comparison between those two people. Plus you can check the boxes in the select column for any number of matches and then submit them to the multi kit analysis using the orange “Submit to Multi Kit Analysis” button above the name column on the left. To get this clustering tool all you need is a Tier 1 membership and a kit number. It is listed at the bottom of the Tier 1 tools. Personally I like to raise the thresholds to a top 200 and a minimum of 20, but try the defaults first and see what is best for you.

One of the nice things about the cluster output from Genetic Affairs is that it lists all the cluster members in groups below the graph with the number of people in each tree (clickable) and any notes you made on the Ancestry profile. The MyHeritage version also has those cluster lists with your notes and the tree sizes; and of course they are clickable to the match (which may even have a theory of family relativity for you!) and the match’s tree. The down side is that you cannot select the parameters for the clustering yourself, they are preset. Possibly only power users care about that!

Extract from my list of matches in each cluster at MyHeritage

An exciting new feature for those looking for one unknown parent or grandparent is the ability to cluster just your starred Ancestry matches when using the clustering tool at Genetic Affairs.  Click here for my previous post about that tool. There now is a checkbox on the page where you select your parameters for getting a cluster analysis.

Newat Genetic Affairs is the checkbox for only starred matches when starting a cluster analysis

It is a common practice to star (mark as favorites) the matches that seem to be from the family of an unknown parent or grandparent at Ancestry. Usually these are determined by looking at who matches or doesn’t match a close relative like a half sibling or else by eliminating matches from the known side. Sometimes you can use ethnicity. I am currently helping someone where the known side is Jewish and the unknown side is Italian and those are easy to separate.

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