Since 1998, genetically modified papayas have been cultivated in Hawaii, USA. They are resistant to a domestic viral disease. In the EU, genetically modified papayas are not approved.
Cultivation of virus resistant papayas in Hawaii: On the left, rows of conventional papaya trees infested with the Ringspot Virus. On the right, genetically modified virus-resistant plants of the variety "Rainbow"
In the late 1980s, the University of Hawaii began developing a papaya cultivar resistant to Papaya Ringspot Virus. To do this, certain viral genes encoding capsid proteins were transferred to the papaya genome. These viral capsid proteins elicit something similar to an "immune response" from the papaya plant. These new, genetically modified papaya plants are no longer susceptible to infection, allowing farmers to cultivate the fruit even when the virus is widespread.
The first virus resistant papayas were commercially grown in Hawaii in 1999. Transgenic papayas now cover about one thousand hectares, or three quarters of the total Hawaiian papaya crop.
Genetically modified papayas are approved for consumption both in the US and in Canada. Several Asian countries are currently developing transgenic papaya varieties resistant to local viral strains.
At this point, GM papayas are not approved in the EU. Until now, no application for approval has been submitted. Therefore, importing and marketing genetically modified papayas is not permitted in the EU.