[Moonshadow]

Well in the beginning of the movie when Rachael takes the Voight-Kampff test given by Deckard at the Tyrell Corporation, Deckard says to Tyrell "does she know?" Then they discuss how many questions it took to determine that she was a Replicant.
I am dying to see the sequel because perhaps those questions will be definitely answered, especially the one about Deckard. But Rachael was definitely one because Tyrell said so in the movie.

I remember the test was to determine if the replicants had empathy, which they did not possess, they could implant memories, but they could not make them "human".