If you have a DNA test performed and it shows 35% German ancestry, 25% Irish ancestry, 10% Scandinavian ancestry, and the rest from the Middle East, does that mean your brother or sister will show exactly the same results if they also take a DNA test? Actually, the answer usually is “no.”
How can full-siblings have different ethnicities when they have the same parents? It’s a consequence of the complex relationship between genetics, ancestry, and ethnicity.
It is usually because one sibling received more or fewer genes from one parent than the other. In contrast, the sibling may have received more genes from the second parent and fewer from the first.
Confused? An article and a graphic in the Genealogy Explained web site at http://bit.ly/2NnKr29 will explain it.