Yes, HELIXES is a Scrabble word!

Letter values in Scrabble US: H 4, E 1, L 1, I 1, X 8, E 1, S 1.

Is it a valid word?

HELIXES is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a curve that lies on the surface of a cylinder or cone and cuts the element at a constant angle
a structure consisting of something wound in a continuous series of loops
type genus of the family Helicidae

Also: genus helix.