Stalker0 said:
. I assume a human has two human genes, an elf has two elf genes, and a half elf has one of each.
If you're going to assume that something as mundane and scientific as genetics has any relevance in a fantasy world, you ought to put just a touch more thought into it...
The state of being an orc is going to have a lot more than a single gene controlling it. You're talking about something more similar to dealing with different breeds of dog, where there's mixing of many traits.
A human/orc breeding produces a thing which, on the whole is half human, and half orc.
A human/half-orc breeding produces a thing that's three quarters human, one quarter orc. Halfway between a human and a half-orc. Being far more human than orc, you can probably just imagine that these are just humans.
Simiarly, a orc/half-orc pairing is 75% orc, 25% human. Probably just call it an orc.
Just as reasonably, you can disregard genetics entirely, and call it what you want
