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annalubov
07-12-2017, 07:40 PM
on ancestry report there is feature with "mom and dad" with a colorful wheel. What does it mean?
I am still a newbie :)

my biological parents' heritage in unknown btw.

Dorkymon
07-12-2017, 07:51 PM
They can show you where your ancestry comes from if you test one of the parents.

annalubov
07-12-2017, 08:13 PM
They can show you where your ancestry comes from if you test one of the parents.

Do they have to be tested in general? Does the image shows actual mom's heritage and dad's in my case. Or is it by default?

greerpalmer
07-12-2017, 10:24 PM
Do they have to be tested in general? Does the image shows actual mom's heritage and dad's in my case. Or is it by default?

Not really a feature- just an example of additional information you could get from testing your parents. There is no way to break out maternal/paternal DNA on atDNA without testing the parents

geebee
07-13-2017, 09:04 AM
Do they have to be tested in general? Does the image shows actual mom's heritage and dad's in my case. Or is it by default?

It does not show the parent's heritage. And, it may sometimes be flat-out wrong. This is especially true when only one parent has been tested.

I've seen instances in which an ancestry the child has but the tested parent does not, is still partially attributed to the tested parent. This will be shown both by the percentage attributed to that parent, and the placement of the segment in either the upper or lower half of each pair of chromosomes.

If there isn't at least one tested parent, which half the segment is shown in is not a reliable indicator of which parent the segment came from. But when there is a tested parent, it's supposed to be. So, for example, contributions from my father are shown in the bottom half; the segments in the top half are attributable to my mother.

In at least two instances, segments which are clearly the same segment are differently attributed for different siblings. For example, four out of my father's six offspring inherited a Native American segment on chromosome 15 that is attributed to our father (who Ancestry Composition reports as 100% European) for three of the four. But it's attributed to our mother for the fourth.

It's clearly the same segment, and must be from the same parent. Since I passed this same segment on to my daughter -- who shares no DNA with my father on chromosome 15 -- it clearly must be maternal. Yet I'm one of the ones for whom the segment is supposedly paternal.

(The six siblings, by the way, only show in the neighborhood of about 2% each of Native American ancestry. This is in the form of about six to eight segments. My mother has documented Native American ancestry from both of her parents, so it's unsurprising. Our father, as I said, is reported by Ancestry Composition as 100% European, and has no Native American segments on chromosome 15 or anywhere else.)

I'm not sure just why the same segment is attributed differently for different offspring. It's possible it is related in some way to my father's child phasing, which would have been done using just one of us. Which one, I don't know.