» Thu Dec 08, 2011 2:33 pm Some concept of inheriting the parent's traits exists, but can we really call it genetics? The Earth idea of zygotes merging and supplying an equal number of traits obviously doesn't work to produce the children of Nirn, which favor their mother's race. I suppose you could come up with some 'scientific' explanation (gametes not having equal amounts of DNA? Post-conception RNA splicing on behalf of the mother's cells? I'm making this up based on what little I remember of bio), but whatever solution is made it would almost certainly turn out to be needlessly complex.
Although it makes little evolutionary sense, it's not a scientific impossibility to have a system of genetics where the mother's DNA takes a heavy amount of precedence over the father's. In a way, this is exactly how the "Y" chromosome works - men are more susceptible to certain genetic maladies because that stunted final chromosome means the mother's "X" chromosome has no balancing or mitigating factors.
Also keep in mind, there's also good ol' http://en.wikipedia.org/wiki/Parthenogenesis, where mothers don't even need any outside genetic material at all, and may simply become pregnant on her own under proper conditions. Because the DNA splits off, randomizes slightly, and recombines, it's not even "cloning" per se, and you can still have genetic changes over time, although they will be slower.
The concept of vampirism or lycanthropy being hereditary may be a little silly, however. Actually, it may be better to look at it through the metaphor of an STD - a mother who contracts an STD may give it to her child in the womb. In the case of the half-vampire in Oblivion, it may just be that the mother was healthy enough to "resist" vampirism, but the embryo was not, and was infected/cursed at conception.
