EDIT: After some thoughts and reading a few comments, there is possibly a lot more that could go into this video regarding genetics and Alicorns, but like I said, I don't want to delve too much into it at this time, maybe later after Season 2 is over and we have more information.
As someone said:
"If you have a pegasus who carries horn genes and a unicorn who carries wing genes, like so: hhWw x Hhww It would be possible for them to have alicorn sons, right? I mean, without the alicorn mother rule (maybe the guy would have the genes but 'alicorniness' wouldn't manifest, or maybe he'd die at birth, only alicorns being able to 'mother' an alicorn).."
Yeah, that does seem like it would work. In fact, it would produce a ratio that would actually be higher for alicorns. I'm guessing that there is more to alicorns besides just these two genes though, and that's why we haven't seen them.
The ratio that would produce would actually be evenly spread... 4:4:4:4
A short video explaining how I think pony genetics work for wings and horns since we now know they can breed and produce fertile offspring.
(Crap, I just realized that I mispelled alicorn in the second slide that has it... oh well, it's not there long.)