In some parts of the world flooding or drought can wipe out an entire crop causing food shortages, price rises and in the worst cases famine. Even when not struck by such disasters, pests and diseases may reduce crop yields. Teams of scientists across the world have been mapping the genetic makeup of a variety of staple crops. They are using this knowledge to develop crops with different properties such as resistance to disease or drought.
However, in many countries altering the genetic makeup of living things is met with concerns both ethical and regarding the safety of genetically modified crops. Each country therefore has its own set of regulations for the approval of any genetically modified crop.