Meyer stated in an interview that what set her vampires apart from others within fiction is that they sparkle.
Q. What sets your vampires apart?
Stephenie Meyer: "Well in general, because I know there's a lot of varying legends, you know, and there's the ones that turn into bats
and mist and there's the ones that are more concrete. In general, my
vampires don’t have fangs and they don’t need them. You know, strong
as they are it’s kind of unnecessary. They're fairly indestructible.
Wooden stakes and garlic are not going to get you anywhere. They don’t
sleep at all. They're never unconscious. They have no periods of
unconsciousness. And the sunlight doesn't harm them, it just shows
them for what they are because they sparkle in the sun."
I've uncovered no notable instances of vampires having sparkly or twinkly skin in any other media prior to this.