Scientists at the University of Illinois are changing the sex of papayas. Papayas already grow as male, female, and hermaphrodite. To help frustrated farmers to cut costs and to grow more hermaphrodite papayas (which is the type sold commercially), scientists are changing the sex chromosomes of papayas, so that more hermaphrodite papayas are produced.

The are two reasons they're doing this:

1. The sex of a seed is not known until the papaya plant has flowered.
2. The hermaphrodite papayas do not always produce more hermaphrodite papayas.