Unintended consequences for genetic engineering; - Kim Harrison's series with the tomatoes turning a bunch of people into dead but the people that are vampires and stuff can survive supernatural creatures this leads to tomato based products being super culturally relevant, for example the supernatural are the only ones willing to eat pizza or pasta sauce, even though the disease has been eradicated. a character who is fully human who actually is willing to eat pizza with the protagonist is a good example of using willingness to eat tomato as a proxy for culture. - Octagonal Raven by Modesitt Again the focus should be on 5 Consequences... And then books that demonstrate. Not 5 books that demonstrate consequences. That's how to set it apart; because obviously it's a common theme in sff...