Newbie questions

[laineybug]

Gosh, you guys, I came here to ask some basic questions, started reading some of the threads to see if I could find answers on my own and hours slipped away. How utterly fasinating!

I just ordered a DNA plus kit for my dad and am really looking forward to his results. I feel an urgency to get it done as he is 85, not in the best of health and doesn't have any male descendents.

Anyway, here are my questions

1) I understand that a male can have his father's DNA tested as it comes down on the Y chromosone and his mother's mtDNA tested because it comes down on the X chromosone. Women can have their mtDNA because it is on their mother's X chromosone. But, doesn't a woman also inheirate an X from their father? How does the lab know which X is from the mother and which is from the father?

2) Now this question just came to me as I read through some of the threads. What is the DNA print test and how does it differ from the regular DNA results?

[AngelaC]

Re: Newbie questions

Originally posted by laineybug
Gosh, you guys, I came here to ask some basic questions, started reading some of the threads to see if I could find answers on my own and hours slipped away. How utterly fasinating!

I just ordered a DNA plus kit for my dad and am really looking forward to his results. I feel an urgency to get it done as he is 85, not in the best of health and doesn't have any male descendents.

Anyway, here are my questions

1) I understand that a male can have his father's DNA tested as it comes down on the Y chromosone and his mother's mtDNA tested because it comes down on the X chromosone. Women can have their mtDNA because it is on their mother's X chromosone. But, doesn't a woman also inheirate an X from their father? How does the lab know which X is from the mother and which is from the father?

2) Now this question just came to me as I read through some of the threads. What is the DNA print test and how does it differ from the regular DNA results?

Hi laineybug,

MtDNA is only inherited from our mothers, - which makes it sound as if it has something to do with the X-chromosome - but it doesn't.
MtDNA is the DNA from Mitochondria, which are the little "energy factories" in all our cells. It has it own DNA, seperate from the rest of our DNA.

The DNA print test looks at genes from the autosomal DNA (which is the DNA from the 44 non sex chromosomes), that have different allele/trait frequencies in four different "racial" groups. Basically the test looks at what version of the "marker" genes you have and calculates from that what your "racial" % is in four broad categories.
The test of course cannot identify which ancestors contribute what bits of DNA, and the categories are rather broad. It also doesn't differentiate between recent "admixture" and ancient "admixture". For instance 70% indo-european/30% East Asian might mean 1 Asian grandparent, or it might mean that the person comes from east Europe where the 30% east asian represents ancient admixture.

Hope this helps,

Angela.

[laineybug]

it does. Thanks very much