Something brought up in a thread started by elfkin477 on 07-14-2005 has been in the back of my mind for a while, and I’ve finally decided to ask about it.
First off, here’s part of the OP from that thread
And from there on, everybody agrees that the dad can’t be 1/3 of anything.
So tell me, if you have somebody, and their mother is, let’s say 1/2 Irish and 1/2 Brazilian (I’m just making this up off the top of my head) and the father was 100% Hawaiian, wouldn’t that person be 1/3 Irish, 1/3 Brazilian, and 1/3 Hawaiian?
If you use your example with M&M’s instead of nationalities and have your mother be 1/2 reds and 1/2 greens and your father be all blues, and mix them up to become you, you’ll see the you are 1/4 red, 1/4 green and 1/2 blue.
Using 2 as a divisor, it’s going to be real hard to come up with thirds – ever.
Unless there is a mother somewhere in your ancestry that had superfecundity and had twins from two different fathers, I don’t see how you can get thirds.
And even the above scenario would just be thirds based on not knowing who the father of each twin was.
I understand in America you become a hyphenated nationality if you can find one in your family six generations back, or you have personally borrowed a cup of sugar from someone of that nationality or whatever. So you can become a Canadian-American if you have ever eaten Poutine.
But you’re never going to become officially ethnically 1/3 of anything - I guess it’s down to how affiliated a person feels with a particular culture. I’m officially Norwegian, Scottish-Norwegian by background and pretty much British by affiliation*.
In the case of the example quoted the only possibilities I can come up with are:[ul]
[li]Their immediate family tree is full of mixed nationalities and buy the time they’ve worked out all the fractions it comes to 1/3 of each[/li][li]Parents are of two different nationalities and was raised in a third country[/li][li]Born to mixed nationalities and gained a third from a step-parent[/li][li]Mad as a hatter[/li][li]Desperately trying to appear interesting?[/li][/ul]
But basically, it’s halves, quarters or eights. By the time you get to sixteenths no-one cares unless they’re a geneticist or something.
Cue quick rendition of “Maybe it’s because I’m a Londoner” with ukelele accompaniment
There’s one more (silly) possibility: mutation. Ordinary breeding could initially give you power-of-two fractions that were very close to thirds. Say 85/256, 85/256, and 86/256. Then, with a few convenient mutations happening — shazam — you’re born as 1/3, 1/3, 1/3.
Of course the whole notion is ridiculous when you get down to that fine a level of resolution. It’s not as if every allele has a particular national identity.
For the 1/3 thing to make sense, somebody’s going to have to demonstrate how one can have three biological parents. Even if you get two sperm donors and run their stuff through a centrifuge (or a Cuisinart) and mix their juices up to the nth degree, only one of the sperm will fertilize one egg. So you may not be able to deduce whose sperm it was, but you’ll have to accept that it was one or the other and not both.
I suppose if governor Schwartzeneggar can hold dual citizenship in the United States and Austria, some other enterprising celebrity could pull a treble.
Uh-uh. Even then, you get have your genes from each parent. No matter how screwy your family tree is, your nationalities are the sum of fractions of powers of two. And as yet, your in vitro fertilisation idea isn’t quite possible.
Thanks. I knew I was screwing up the math somewhere. I completely forgot that for each generation, unless both parents are 100% a certain nationality, each nationality is divided in half.
Actually, I think the proper way to do it is divide all nationalities in each parent by half all of the time, and then add up. If your parents are both 100% french, then 50% french + 50% french = 100% french.
What about so-called supermales or superfemales (people with a genotype of XYY or XXX)? Or for that matter Klinefelter’s Syndrome (genotype XXY)? The supermale, for instance, would get two copies of DNA from his dad, so if the dad (who contributes the YY) was half black and half white, and the mother (who contributes the X) was Asian, you would have a perfect three-way split. Or am I misunderstanding these conditions?
These errors are only for a single chromosome. Your DNA has 24 chromosomes, including the two Xes or an X and a Y. If you have one of the conditions you mentioned, then you have a total of 25 chromosomes. In any case, we are dealing with rather small fractions at this point.
I should really look this stuff up before posting. It’s 23 pairs of chromosomes, including the sex chromosomes (one pair) for 46 total. (47 if you’re a mutant.)
If a person told me he had 6 French great-greatgrandparents, 5 English great-greatgrandparents, and 5 Scottish great-greatgrandparents then told me he was 1/3 of each I would ask him why he hates America.
