What is the theme in Oryx and Crake by Margaret Atwood?

Corporate Power is the main theme of the book. In Oryx and Crake, corporations exist separately from the rest of the world. Characters who are lucky enough to work for a corporation can escape the lawlessness and filth of pleeblands and live in an idyllic corporate compound instead. Although Oryx and Crake takes place in America, the novel includes no reference to local, state or federal government. The corporations rule instead. Each compound is a distinct locale, but it appears that the corporations are somehow united because they share a legion of CorpSeCorps agents that work in tandem on such cases as that of Jimmy's mother.