Olive oil comes from olives, corn oil comes from corn and canola oil comes from … canola? Right… sort of. Canola oil is a genetically modified food made from a hybridized version of the rapeseed plant which is a member of the mustard or cabbage family.
Just because you inherited some "bad genes" from your parents and grandparents, doesn't mean you are doomed to suffer their diseases. A healthy diet, including olive oil, can modulate the effect of these genes.