Thursday, January 29, 2015

When a Surrogate is not YOUR Surrogate

For more than a decade we have been using surrogates to help us explore our family histories. We use surrogates to discover DNA information passed down from our ancestors that was not passed down to us. The first major application of this technique was when women solicited close male relatives -- fathers, brothers, nephews or cousins to take yDNA tests to establish the DNA signatures their paternal surname lines.

More recently we have become more creative in the use of surrogates. Almost four years ago I first blogged about using a female first cousin as a surrogate to help me discover information about my paternal grandmother's mtDNA. By so doing I discovered the ethnicity of the female ancestral line of my sixth-great grandmother.

Since then I have used surrogates in other ways.

  • I have tested a male first cousin -- once removed to discover the haplogroup of my maternal grandfather.
  • I have tested a male second cousin to discover the haplogroup of one of my maternal great-grandfathers.
  • I have tested a male third cousin -- once removed to verify the paper trail of an eighth great-grandfather.  

In these each of these instances I was making assumptions that later turned out to be correct. Each of these surrogates were actually related to me in the way I thought they were. By assuming these relations were correct, I was skating on thin ice. I was also violating Dr. D's Rule #1: 

Rule 1. Start with what you know (yourself) and build back to what you don’t know—step-by-step. Don’t skip steps!!

That means what you really know from your own experience. It does not mean things you have heard about as they passed down through the family second or third hand. 
Crash Course in Genealogy (2011), pp. 15-16. 

Continued violation of this rule will jump up and bite you sooner or later as I discovered in the last month. 

Back in 2007 I had helped a female extended family member select a male first cousin -- once removed to test as a surrogate to try to establish where her ancestors might have lived before immigrating to the US in the late 19th century. That original 37 marker yDNA test was followed by a Deep Clade-R test in 2009, and three single SNP tests -- one each in 2010, 2011 and 2012 as we attempted to narrow down the genetic migration trail. Last month during the FTDNA Holiday Sale, a decision was made to bite the bullet and order a BIG Y test for this surrogate to further clarify his haplogroup. As sort of an afterthought a Family Finder test was also ordered. 

The whole house of cards suddenly collapsed. The surrogate did not match his supposed first cousin -- once removed. He also did not match her sister or brother who also were supposed to be first cousins -- once removed of the surrogate. Seven tests and the seventh one under cut usefulness of the other six. 

Lesson to be learned: the FIRST test you should invest in when using a surrogate should be an atDNA test like Family Finder to verify that your supposed close relative is really YOUR close biological relative.

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