I see your point, but I can't resist giving a biology lesson here. (This stuff fascinates me.)
There are several different genes controlling eye color; some are dominant and some are recessive. You get one gene from your mother and one gene from your father. Call the brown-eye gene B and the blue-eye gene b. Suppose both your parents have the combination Bb, i.e., a brown-eye gene and a blue-eye gene. Now brown-eye is dominant and blue-eye is recessive. So if your genetype is Bb, you have brown eyes. So look at the child of these parents. There are four equally-likely outcomes: BB, Bb, bB and bb. The first three outcomes result in brown eyes; but the last outcome gives you blue eyes. So two brown-eyed parents can have a blue-eyed child. Now, to my point: Suppose both parents have the genotype bb. Then the child is guaranteed to have genotype bb. So two blue-eyed parents will "breed true" in producing only blue-eyed children. (Of course, the truth of the matter is more complicated, since there are other eye colors running around that might be recessive to blue.)
The really curious story about genetics and color concerns calico cats. It turns out they don't breed true. To obtain a calico cat, you must combine the "tabby" gene with the gene for black hair. But both of these genes occur on the X chromosome, so to get both, the cat must be female. (Females have two X chromosomes but males are XY.) So all calico cats are female. But not really -- one in every 3500 calicos is male. Turns out that such cats have genotype XXY, they have an extra X.
Well, my eyes are mostly bloodshot. Where did I get that trait???
Anyway, my father is blond haired, blue-eyed and my mother was brown hair, brown-eyed. She obviously was Bb because all three of the children have blue or green eyes. Mine are more silvery-green than anything - like Meg Foster's in "They Live" but not as extreme.
I've always thought that the Holocaust and its aftermath should be studied scientifically. It represented a "shock" to a population that was somewhat different than its surrounding (Middle Eastern Jews in Europe). What I think would be interesting is how a cultural change affects future generations genetically. Not surprisingly, the "Never Again" mentality took hold after the Holocaust and that has to have some effect on the choices Jewish women make in choosing a husband. Do they choose more aggressive men that would be better defenders of them or do they choose less aggressive men because of the disgust with the aggressive Nazis? I guess the mixing with Europeans probably makes any sort of study impossible. Half the Jews I know are blue eyed and many have blondish hair, which would confuse the heck out of Hitler.