Consider the other books by Margaret Atwood in the MaddAddam trilogy (of which Oryx and Crake is the first book): The Year of the Flood and MaddAddam.
Consider other books by Margaret Atwood, including The Handmaid's Tale and The Blind Assassin.
Consider other works of speculative fiction, including Kazuo Ishiguro's Never Let Me Go and Phillip K. Dick's Do Android's Dream of Electric Sheep?