without getting too technical, any remote can be replaced by a universal remote or even the remote you have for another unit, at least almost any remote.
go here:
Directv remote codes for genesis gt-2.0 - Fixya
also, there are some web sites that show you, in technical terms, how they work, how to reprogram them to do anything just about if you want to take the time to learn how. I got 5 universal remotes online for just over 2 dollars a piece, new.