Same parents, 47 % difference?

[jonni7]

Kit 557986 is 53 % Scandinavia

Kit 507022 is 100% Scandinavia

The siblings have same parents. Is this normal ?

[prairielad]

Yes each of you received a different mixture of each parent.
It also depends on what each grandparents background is

[John McCoy]

It's certainly true that siblings will inherit different parts of each parent's genome. To the extent that either or both parents are not 100% of whatever it is that this test is measuring, the children will end up with varying amounts.

As outsiders, we don't actually know what is being measured by FTDNA's admixture algorithm. We don't know that the SNP's used to define, say, "Scandinavian" origins, are equally distributed across all chromosomes, or how many such SNP's there are, or how they line up with living people who are actually Scandinavians. In other words, we don't know what is being measured or even how to test the accuracy of the results.

Anecdotally, some people find that the results are completely consistent with what they already know from their own genealogical research. Others find the results completely at variance with their pedigrees. And there are a lot of people in the middle.

There are many other "admixture algorithms" (several of them, with variations, are available for free on the GEDmatch web site). Each has its fans, presumably because it gave them results that made sense to them. Whether any of them is actually better than the others, I don't know.

[ntk]

I would retest elsewhere and compare if you are have an interest in these results. See my results in prior thread, FTDNA is alone in giving me a phantom 53% Scandivanian, 0% Western European makeup. I don't think the European breakdown on myOrigins can be trusted in the slightest. It's certainly true that siblings can by chance inherit very different segments from grandparents on either side, but this 53 versus 100% difference is much more likely accounted due to the well-known oddities in FTDNA's admixture analysis. Such a large difference would unlikely to be due to chance alone, rather than chaotic influence on a half-baked analysis.

[jonni7]

We have now testet the 3 th sibling and the results are:

Sibling 1: 100 % Scandinavia

Sibling 2: 53 % Scandinavia 47 % British

Sibling 3: 89 % Scandinavia 11 % Western/Central Europa

[Yde]

100 % Scandinavian - from where?

Where are the parents to this 100% Scandinavian exactly from?

How many 100% Scandinavians are known by "the system", and where were their parents born?

[prairielad]

My Grandfather is 100% Scandinavia, his father born in Norway, his mother in Sweden.

My Mother (her mother English)- 69% Scandinavia,29% British Isles, 2% Eastern Europe

My Aunt 1 - 85% Scandinavia, 11% British Isles, 4% Asia Minor

My Aunt 2 - 69% Scandinavia, 16% British Isles, 15% Eastern Europe

My Uncle - 88% Scandinavia, 7% Southern Europe, 5% Eastern Europe

Their mother(my Grandmother)(English)- 69% Scandinavia, 7% Southern Europe, 5% Eastern Europe.

Me (Scottish/Irish and German Bukovinian paternal side)- 63% British Isles, 34% Scandinavia, 3% Eastern Europe

Edit
to add

My Father (Scottish/Irish father, german Bukovinian mother) - 57% British Isles, 15% Southern, 13% Eastern, 12% Scandinavia, 1% Finland, 2% Central Asia

[jonni7]

The three siblings have only Norwegian ancestors as far as we can see in the big paper tree.