Cannot see why. The laws of genetics were created by Him, and I can see absolutely no reason why those laws don't apply to humans as much as to any other member of the animal kingdom.
We ARE animals, though we are not JUST animals.
Nobody knows what the “laws of genetics” are except God. The eugenicists’ folly is already on record; no modern scientist has successfully decoded the entire program written into then DNA of any being let alone man’s, and to presume that eugenics, with its lack of such knowledge, is superior has to be absurd. What influences and upbuilds the behavior of man more is the strong and stable family, whereas the lack thereof destroys him. And as far as animals go, the characteristics bred in and out have nothing to do with intelligence, since they run on instinct. Gifts of human intelligence are exactly that—gifts.