Some people eat, sleep and chew gum, I do genealogy and write...

Monday, April 25, 2016

Analysis of a Relationship for DNA Testing

As I continue digging deeper and deeper into the possibilities of DNA testing as a tool for determining genealogical relationships. It occurs to me that before any testing can be done, there is a need to define one or more specific genealogical issues that could be resolved. At this stage of my investigations and reading, I am not overly impresses with the accuracy of the various companies. It appears that lacking a very specific investigative target, a general DNA test is more of shotgun approach than a well-aimed single shot and as anyone who has shot a shotgun knows, the cluster disbursement of pellets increases with the distance of the target.

Of course you can ignore all this and blindly get a DNA test. The results will be a general statement of the percentage breakdown of the regions of the world from which your ancestors may have come. This may be helpful or even startling to some, but what about those of us who have been doing extensive research for years and have a very good idea of our ancestral pool? Here is a partial description of the expected results from a test from FamilyTreeDNA.com:
Family Finder matches are other individuals in our database who have also taken the Family Finder test and who, through autosomal DNA comparison, are found to share a common ancestor with you from ANY of your ancestral lines within the past five generations. The names and emails of your matches, an estimate of how closely related they are to you, and any genealogical information they have uploaded are provided to you in order to collaborate on genealogy and get past genealogical brick walls.
From my standpoint the key statement here is "ancestral lines within the past five generations." Why does this statement mean anything to me? I have extensively documented all of my family lines for at least six generations. This information is readily available online and from time to time, I connect with people who are related or possibly related back more than six generations. My least documented lines begin having issues only in the seventh and eighth generations. So, if you are doing your own research, and you have a family tree on MyHeritage.com, Ancestry.com or FamilySearch.org, you can readily determine whether or not we are related, without a DNA test, by simply looking at the matches or doing some descendancy research.

Further there is absolutely no controversy over the origin of any of these six generation ancestors. Positive, documented, birth information has been found and is provided online. There is one sole exception to this statement: my Great-grandfather, Marinus Christensen. As I have written previously, Marinus Christensen, (b. 1863, d. 1927) from Denmark, is persistently characterized in family stories as "adopted." Marinus was one of the three children of Jens Christensen and Karen Marie Johannesen. So far, my paper research has not resolved this issue. So the question is, can DNA testing be of any help in resolving the question of adoption. You would probably, if you have been to some DNA presentations, say why yes, of course. But let define the problem with more specificity.

My father is a descendant of one of the two Christensen daughters on his mother's side. This means that neither he (nor I) inherited any Y-Chromosomes from the Christensen males. My father's mother's mother was the daughter of Jens Christensen. On my own mother's side of the family, her mother was the daughter of Marinus Christensen. So I have no Christensen Y-Chromosomes at all. As a matter of fact, my only ancestral connection with Denmark is entirely through female lines. My father's mother was the daughter of Henry Overson, whose father, Ove Christian Ovesen (or Oveson) came from Denmark and married Jens Christensen's daughter. So I have no Y-Chromosomes from that line either.

Now here are the possibilities.

  • Marinus Christensen was totally adopted and not directly related to the Christensen family
  • Marinus Christensen was a "relative" and adopted by the family
  • Marinus Christensen was the son of one of the two Christensen daughters, who, by the way, were old enough at the time of his birth to be the mother
  • Marinus Christensen is the daughter of Kirsten Marie Pedersen and so was not adopted at all

Absent any possibility of my having a Y-Chromosome, which DNA test would resolve this issue? Resolution of this issue essentially determines if my parents were second cousins or unrelated. Bear in mind, that there are no known male descendants of Jens Christensen except Marinus.

Now that is one of the exact questions I am writing about when I say that a specific genealogical issues needs to be identified and defined in a way that can be resolved with DNA testing. Absent this why would I want to know generally where my family came from? What would I learn if a DNA test, if it were at all possible, told me I had Danish Ancestors? By the way every one of my documented lines, with the exception of these two Danish families, come from England, Scotland, Wales or Ireland. The earliest continental European ancestors are 10 generations back and may have come from the Netherlands. But since, I have documentation verified only about six or seven generations back on every family, I would have to leave open the possibility that there is another line somewhere out there from the continent. Would a DNA test help me at this time?

No comments:

Post a Comment