While there was not much "intermarriage" between Jews and their fellow Europeans until modern times, there was certainly some. And add into that illegitimate births from the occasional affair, rapes, etc. I think there's much more "hidden distant Jewish blood" in Christian Europeans and vice versa than we know. How else do you explain that Ashkenazim look more like Europeans than Arabs and while they do not have the frequency of blonde hair/blue eyes of Swedes, few if any Arabs have them at all. Even Hitler knew this, why else did he need gold stars to separate them from his so-called "Aryan superman". This just proves the fallacy of racism.
Brazilian head of UN peacekeeping force in Haiti dies of heart attack (Reuters)
from the article: DNA tests reveal Hitler's Jewish and African roots