Vampires and werewolves aren't enough? They're typically 'fantasy' sure, but if you follow the definition of science, both are created through biological transformations - that's the science-y part, since today, in our world, there is NOT a way to change someone from a plain old homosapien to a blood-sucking fiend or a being that transforms itself into a giant ugly wolf 3 nights a month. It just don't happen.
(I don't know why it's always thought that 'science fiction' only refers to 'technology' - it doesn't.)
That should get you started - broaded the definition of 'science fiction'. You may have to research to get some of the bio and chem terms lined up, but that shouldn't be a problem, right?
