There should be a blending of phenotypes. I.e., whatever pigment gene is making Dunmer grey or blue or whatever should blend with, say, a white Cyrodiil to make an intermediately grey-white pigmented child. You kind of see that with the Grey Prince in Oblivion.
The genes would blend together in different ways: recessive epistasis, dominant epistasis, complete dominance, redundancy, complementary interaction. Throw in polygenic to make them continuous genes (good bit of review there for me, thanks for reading all that.)
It just doesn't make sense. And even if the child's "race" were completely six-linked on the mother's side, (and the autosomal chromosomes coded for scrambled eggs,) it's not like the X chromosome of the fathering Cyrodiil would just sit there and do nothing in daughters. Mendelian genetics just do not apply here.
So help, Bethesda Forums! Console this procrastinating college student who should really get back to his genetics textbook!