Birthmarked (Birthmarked #1) by Caragh O'Brien

In the future, in a world destroyed by the harsh sun, there are those who live in luxury inside the walled Enclave and those, like sixteen-year-old Gaia Stone, who live outside -- struggling to survive. Each month the people outside the wall must deliver a quota of babies to the Enclave, to be raised by parents within and brainwashed to forget about the world outside.

This is the way it's always been, and the way Gaia thinks it should be . . . until her parents are arrested on suspicion of hiding a code, a code revealing the secrets of the "advanced" babies. Realising she is her parents' only hope for survival, Gaia ventures inside the wall to rescue them. But she soon discovers that the Enclave is not as perfect as it appears, the gene pool has become too small and genetic irregularities are developing -- something the brutal government wants to stop. At any cost. Can Gaia break the code and discover the truth, before it's too late?

Genres: Young Adult - Dystopia - Fantasy - Science Fiction - Romance - Post Apocalyptic - Adventure