Question in regards to results of a DNA test?

+4 votes
99 views
I found out yesterday that my father got his DNA test results back (haven't seen them). I know pretty much NOTHING about this topic, so please be gentle in your responses.

He said that it came back that he is English, Welsh, Irish & Scottish.

What I do know, I think, Is the male dna is passed from male to male, (if I read that right). So here's my question, is it possible for some of the male dna to not be passed down?

The reason for my question is, his 2nd Great Grandfather (my 3rd) is suppose to have been born in Alsace-Lorraine, France, before it became part of Germany and it's been stated by numerous family members that it is through him that we have German dna.

And no I do not know what kind of test he took because he was in a really noisy place and I couldn't ask.
in The Tree House by T Counce G2G6 Mach 6 (64.5k points)

2 Answers

+8 votes
 
Best answer
First up, don't get too wound up about the ethnicity estimates, they are all over the place - for instance with one company my Dad is mainly English and I am mainly Ireland/Scotland/Wales with no England; go figure!

This will most likely be an autosomal test, those genes you get from both parents. That's the most common type of test. The male test is the Y test, which fewer people take.

There are lots of really good websites to ease you into the subject; but be careful it will get you hooked.
by Chris Hampson G2G6 Pilot (105k points)
selected by Pip Sheppard
Thanks...he married into what I believe is English family (we're having a little bit of a dilemma with that part of the tree)...so that kind of makes sense. I'm not going into any web pages until I get mine done and that's not going to be for a while.
+6 votes

Yep; what Chris said about not getting wound up over the admixture estimates. Some thoughts at this post, titled "Should You Trade Your Lederhosen for a Kilt?"

The Y-chromosome (inherited only from father to son to son, etc.) and mtDNA (mitochondrial DNA; inherited only from the mother, although we all have mtDNA) are the only types of DNA that are passed along with no recombination and mixing. Autosomal DNA--what really makes us us, and the kind of test your father took--is basically run through a Waring Blender at every birth event.  :-)  Good thing, too, because that mixing allows enough genetic diversity for small populations to survive...think isolated Pacific islands or the earliest Native Americans.

We get (a randomish) 50% of our autosomal DNA from each of our parents. Which means about 25% from each grandparent. But now it's already a little bit variable: it isn't exactly 25%. From our great-grandparents, we get an even more about about 12.5%. Your dad's 2g-grandfather would have contributed about 6.25% to your father's total genetic makeup.

When you glance at that link above, you'll see that, while not exactly smoke and mirrors, estimating origins from DNA admixture is, frankly, more art than science at this stage of the game. Is it fairly accurate with broad, continent-wide approximations? Sure. It isn't going to place you in Southeast Asia if you're Western European. But as an example in this case, the Germanic Angles and Saxons and the Norman French all have pretty long histories of occupying England. And no one whose family hails from Scotland or Ireland or northern England should be even mildly surprised to find Scandinavian DNA.

But even so, that 2g-grandfather from Alsace-Lorraine can only give his 6.25% to the total genetic pool (half again to you, so 3.125%). And my bet is that when you get your results, you'll compare them side-by-side with your dad's and wonder why the distributions look so different. Label it as "for entertainment purposes only."  ;-)

by Edison Williams G2G6 Pilot (309k points)
I had already read most of what you said Edison...but that last part made me laugh out loud.
I swear I came up with that phrase, but even if I didn't it's true: Admixture (that's what all those percentages are called) are wildly inaccurate, probably CAN'T ever BE accurate (no matter how much they work on it), and therefore have no real genealogical value. It is truly "for entertainment purposes ONLY!"

That's the aspect of the test that's advertised, but it's important to realize that there are OTHER aspects of the test that are VERY useful, genealogically. Specifically, you get a list of other test-takers who match your DNA, as well as a quantitative number that tells you how WELL they match. If it's AncestryDNA, there's something called DNA Circles that can be helpful too.

Since a Y-DNA test is - by definition - confined to a tiny slice of your ancestry (your paternal line), the fact that admixture is in the results tells you right away that this is NOT a Y-DNA test, so the talk about "male DNA" being passed down is not relevant, regarding his test. This has to be an autosomal test - involving, at a minimum, the 22 pairs of chromosomes that don't determine sex.

I should also add that since your father is a generation back from you (again, by definition) HIS DNA is inherently more useful for your genealogy on his side than yours possibly can be. So if he's willing to share his results, there's no reason at all to wait on yours.

As far as the case of your dad's gt-gt grandfather from Alsace-Lorraine, the value of the DNA result is that if you can identify other descendants of that ancestor in your matches, it confirms that you really are his descendant. Further, some of those other people you match might have invaluable additional information about him.

"I swear I came up with that phrase... "

Well, Frank, in the context of consumer-direct DNA testing the phrase dates back to at least February 2015 in a Gizmodo article. Let me just take a moment to consult document number 9134/18, the Proposal for a Directive of the European Parliament and of the Council on Copyright in the Digital Single Market...

(⊙_◎)

(It's Monday. There's gotta be humor somewhere; right?)

Related questions

+8 votes
2 answers
297 views asked May 9, 2018 in WikiTree Help by Kaylee Robinson G2G6 Mach 2 (24.5k points)
+1 vote
2 answers
+4 votes
0 answers
0 votes
2 answers
116 views asked 3 days ago in WikiTree Help by Banele Mlungu G2G Crew (370 points)
+5 votes
1 answer
63 views asked Jul 26 in WikiTree Help by Joel MacDonald G2G2 (2.3k points)

WikiTree  ~  About  ~  Help Help  ~  Search Person Search  ~  Surname:

disclaimer - terms - copyright

...