GM Papaya: Sweet Success 

The papaya owes its survival to the biotechnology industry. Early in 1993, the papaya ring spot virus threatened to wipe out the entire crop on the island of Hawaii. Papaya trees infected with the virus produced a small number of sickly papayas with “ring spots,” and their usually lush leaves were replaced with shriveled ones. Nothing could stop the virus, herbicides and physical barriers were not able to slow its spread. The $45 million industry, a vital part of the island’s economy, was on track to be wiped out.

Papaya infected with Ring Spot Virus


            Scientists at Cornell struggled to find a solution for this deadly threat, and finally turned to genetic engineering. They identified a gene in the ring-spot virus that coded for a harmless protein coat to be made. The gene was then spliced and inserted it into a papaya leaf using a ‘gene gun,’ a crude technology compared to what we have today. Having isolated the gene, scientists created tens of thousands of copies, and mixed them in with tiny tungsten balls, a material to which they would stick. Then, they used compressed gas to fire the ‘ammunition,’ the tungsten balls, at the ‘target,’ a single papaya leaf. Upon contact, a small percentage of the genes were incorporated into the cell, creating the first GM papaya.


A variety of GM papaya now grown in Thailand           

Scientists tested the transgenic papayas in the lab by rubbing its leaves against those of an infected papaya. Remarkably, the GM papaya grew tall and lush, showing no signs of the ring-spot virus. Next, the GM papaya had to be field tested to show that it would have no adverse effect on neighboring plants or the environment. A local farmer was chosen to oversee the testing, and the results were extremely favorable.


            The team of scientists then negotiated a patent deal with Monsanto, which owned the rights to the gene that had been spliced into his transgenic papaya. However, the fight was not over, as some countries like Australia refused the import the GM papaya, claiming that it was not pure food and could be harmful if eaten. But when the GM papaya was analyzed molecule by molecule, it was found to be substantially equivalent to a regular papaya, that is, chemically equivalent.


            The papaya industry in Hawaii had been saved by a new technology, genetic engineering. Shortly thereafter, large biotechnology companies realized that transgenic crops were the future, and began to invest hundreds of millions of dollars in research. Today, GMO’s can be found everywhere. So next time you take a bite out of a papaya, think of how sweet genetic engineering is.  

 Citation 12 (Harvest of Fear Video)

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