Category Archives: DNA match

Skeptical? DNA Doesn’t Lie.

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So, what did it mean?

50.0% shared, 23 segments

23andMe tests autosomal DNA. To break it down as simply as possible (I’m not a scientist and most of what I’ve read about DNA and genetics goes right over my head, so it helps me to keep it simple), the majority of our DNA is autosomal DNA. An autosome refers to numbered chromosomes, as opposed to the sex chromosomes. We all have 22 pairs of autosomes and one pair of sex chromosomes (the X chromosome and the Y chromosome).

The examination of one’s autosomal DNA is highly useful for genealogical purposes. If you share identical segments of DNA with another person, you share a recent common ancestor. The length and number of these identical segments will predict how close the relationship is. The more autosomal DNA that you have in common with another person, the more closely related you are.

A child receives 47-50% of their autosomal DNA from each of their parents, and similarly on average a child receives about 25% of his autosomal DNA from each of his four grandparents. The chromosomes recombine, or mix, as they are passed down from parent to child, so the size of possible shared segments gets successively smaller with each generation.

So check this out:

50% Mother, father, siblings
25% Grandfathers, grandmothers, aunts, uncles, half-siblings, double first cousins
12.5% Great-grandparents, first cousins, great-uncles, great-aunts, half-aunts/uncles, half-nephews/nieces
6.25% First cousins once removed, half first cousins
3.125% Second cousins, first cousins twice removed
1.563% Second cousins once removed
0.781% Third cousins, second cousins twice removed
0.391% Third cousins once removed
0.195% Fourth cousins
0.0977% Fourth cousins once removed
0.0488% Fifth cousins
0.0244 Fifth cousins once removed
0.0122% Sixth cousins
0.0061% Sixth cousins once removed
0.00305% Seventh cousins
0.001525% Seventh cousins once removed
0.000763% Eighth cousins

(Data from International Society of Genetic Genealogy.)

If you are wading through the vast sea of DNA testing to aid your search, I would recommend reading author and adoptee, Richard Hill‘s website, guide and book, Finding Family.  His story is nothing short of amazing.  He searched for decades and finally found answers through DNA testing.  His results were not at straightforward as mine in the beginning–an adventure for sure. He started his DNA search when the science was just starting to evolve and he followed it through its evolution, using all of the available testing sites and sorting through all of the available information.  Mr. Hill has generously compiled all of the useful and invaluable information and has made it available to anyone who is searching.  For free.

I spent an entire weekend researching and trying to figure out what “50%, 23 segments” meant (thank you technology and Richard Hill!).  I was convinced that the Father that 23andMe found was my biological father.  Was he convinced?  Not so much.

Still Untold . . .

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Last week I turned fifty.  Fifty?  Eeeek.  No one has flat out asked me if I’m having a mid-life crisis.  I must be holding it together pretty well.  Or maybe it’s just so obvious that no one wants to ask.  Don’t look her in the eye–she’ll crack, for sure!

I’d call it a kind of mid-life identity crisis.  It’s been about 22 years since the second letter from Margaret.  Okay, I’ll just go ahead and say the word I keep avoiding: Rejection. It’s a word that is commonly used in the adoption community, but I refuse to label her treatment of me as “rejection.”  She didn’t reject me, she rejected the idea of me.  She didn’t even know me.  How could she reject me?

To be relinquished at birth for adoption is one thing. That’s Margaret rejecting the idea of being a mother.  She was young and unprepared (not to mention a little preoccupied with serving a prison sentence), and a baby just did not fit in her plans.  Adoption was her salvation (and mine).  But to be rejected later in life by the woman who gave birth to me –to be rejected as a grown, rational (for all intents and purposes) adult asking questions about the very core of my being, seeking answers that most people take for granted, is something completely, utterly, and abhorrently different. I read an article some time ago written by another adoptee who described the feeling of rejection simply, but completely:

Me: I exist.

Margaret: I wish you didn’t.

Exactly.

I can’t control how Margaret feels.  I can only control my reaction.  And I’ll admit it hurt . . . but I’m not the type to kick something around forever.  It happened once (well, maybe twice . . . or 3 times), but my life is full of other moments.  Great moments.  Pretty darn good moments.  Why wallow in it?

Zach is now 22 years old.  He’s out on his own, happily finding his way with his music.  I’m proud of him.  A lot of other stuff has happened in the span of those 22 years.  By stuff I mean life.  Divorce, remarriage, another son.

Garrett (son number 2) is now 13.  When he was little, everyone said he was the spitting image of his dad.  He still looks like his dad.  Light hair, blue eyes, fair skin . . . once again, I was gazing into the face of my child looking for similarities and any sign of familiarity. Nothing.

Identity crisis or not, I have a great family and things are pretty peachy.  Over the years, I didn’t think too much about Margaret or my biological origins.  I was too busy with the here and now–the good stuff.  My boys were growing; they were keeping me busy.  And you know what else happened over the course of these years?  Science and technology happened.  All kinds of science and technology.  On the technology side, computers are now everywhere, connecting everything and everyone. The world wide web is constantly evolving, with its growing data bases, easy access to public information, instant communication and sharing of personal data via social media.

On the science side, I have been especially fascinated with the advancements in and evolution of DNA testing.  My husband, Guy, is a prosecutor who works with people who do forensic DNA testing.  Forensic DNA testing has enabled old cold cases to be solved in an instant!  How cool is that?  Well, it’s cool, but I wasn’t as interested in that as I was interested in the way DNA testing was being used for health and genealogy research. Talk about an evolution.

DNA genetic testing may be able to predict risk for certain diseases and medical conditions. This would be helpful. In addition, DNA testing can reveal information about family background and familial traits, ethnic heritage, and ancestral history. And finally, the newer autosomal DNA testing has become a tool that can accurately identify relationships between family members by comparing DNA segments.  Put technology (easy access via the internet) and DNA testing together and you’ve got . . . big business.  The bigger the database to compare your genetic results (thank you, internet), the more useful results you’ll get!  Genius!

Why not?  It would be great to finally have some information that might shed some light on my health and predisposition to particular illnesses. I sure wasn’t going to get that information from relatives. My boys are entitled to this information, as well!

As technology has evolved, prices for the DNA genetic testing have come down.  What used to cost nearly $500 is now $99.  I went with 23andMe.  I spit in a test tube and sent it in.  And then things got weird.