genealogy question

[DeusxMac]

davester wrote:
DeusxMac is the god of third grade arithmetic (not that there's nothing wrong with that).

"Not...nothing" So there IS something wrong with being a third grade god?

[space-time]

but if there were some Chimeras in your family tree?

[PeterB]

Just for the record, as a geneticist, I don't see how anyone can claim to be "99.5%" anything. That's a problem with their science, right there. Sure, some alleles might be more common in some populations, but I think you'd be hard-pressed to be able to accurately define things in that way.

[sekker]

PeterB wrote:
Just for the record, as a geneticist, I don't see how anyone can claim to be "99.5%" anything. That's a problem with their science, right there. Sure, some alleles might be more common in some populations, but I think you'd be hard-pressed to be able to accurately define things in that way.

Peter, there could be some recombination between haplotypes to get 99.5%. At that low percentage, all it would take is a single chromosome exchange on one arm.

No, monogamy doesn't matter in this case. You personally are from a single lineage.

Whether you are biologically related to anyone in your family, well that's another story altogether...

I think the issues with regard to parentage are some of the most critical that 23andme are not dealing with properly. In some march of dimes birth defect studies - these are opt-in studies - as much as 15% of paternity is not confirmed by the DNA tests... My recommendation is to test you and your mom; and ask her honestly whether testing Dad is going to be an issue,,,

[PeterB]

sekker wrote:
[quote=PeterB]
Just for the record, as a geneticist, I don't see how anyone can claim to be "99.5%" anything. That's a problem with their science, right there. Sure, some alleles might be more common in some populations, but I think you'd be hard-pressed to be able to accurately define things in that way.

Peter, there could be some recombination between haplotypes to get 99.5%. At that low percentage, all it would take is a single chromosome exchange on one arm.

No, monogamy doesn't matter in this case. You personally are from a single lineage.

Whether you are biologically related to anyone in your family, well that's another story altogether...

I think the issues with regard to parentage are some of the most critical that 23andme are not dealing with properly. In some march of dimes birth defect studies - these are opt-in studies - as much as 15% of paternity is not confirmed by the DNA tests... My recommendation is to test you and your mom; and ask her honestly whether testing Dad is going to be an issue,,,
I take issue with the idea that there are absolutely nationality- or ethnically-specific haplotypes. So it's not about recombination or anything of that kind. Sure, you might be able to make an estimate, but an estimate is NOT the same as a percentage, and I think it's highly misleading to say that anyone is some "percentage" of anything-- in the same way that it's misleading to say that your dog is 70% cocker spaniel, 20% Doberman, and 10% poodle (I just made that one up!).

I think 23andme has messed a LOT of things up. It's not just about their misleading medical claims, either.

Estimates of nonpaternity vary from study to study, but they've sometime reached the 30% mark.

[Lemon Drop]

My dna test shows that I am 99.5% european

In that context what does "european" mean?

It seems to me that many of us would get dumped into that very broad category, though our origins are undoubtedly more complex (invasions of Europe over the centuries, etc.)

Do they give you any more specific geographical breakdown than that?

Last I heard they had African, Asian, and European, and that's it. It's hard to see how that is meaningful, really.

I was going to have my brother do the National Geo test and give it to him for his birthday, with the additional somewhat selfish reason that this would give my line as well in addition to getting the paternal "Y" side that I would not test for. But the more I read about these tests the more I question the value of the results. Though discovering distant relatives could be fun and interesting, assuming the info is accurate.

[davemchine]

This is a really good discussion. I would like to have additional family members tested and that might happen in the future.

Since there is a lot of discussion about what information is provided in the nationality test I will provide my results below. I don't think there is any sensitive information in that graph.

[Lemon Drop]

thanks, that's interesting.

[N-OS X-tasy!]

davester wrote:
[quote=davemchine]
DeusxMac, I bow before your math skills. Thank you.

DeusxMac is the god of third grade arithmetic (not that there's nothing wrong with that).
It's a tough job, but somebody has to do it.

[PeterB]

I'm still not convinced from that graphic above. Saying, for example, that you are "1.5% Scandinavian" ... what does that mean? Sure, there could be markers or even haplotypes which are more commonly found in people of Scandinavian descent, but that doesn't mean you (or they) are Scandinavian. In other words, someone could have a marker or markers but not really be from that region. (This could happen simply because of migrations, etc.) It's simply not that exact, and giving the data/percentages that way is misleading.

Also... I chuckled a bit when I saw the large swath of medium blue that I'm taking them to mean "nonspecific Northern/Southern European" but which also looks to include a lot of Eastern Europe, for which you'd think they'd have more precise markers. A lot of Jews are from that part of the world, and I'd guess they have separate markers for that, but the likelihood is good that anyone who is Jewish or of non-Jewish European descent is not "pure"... if you know what I mean! (