DANFORTH CENTER CASSAVA VIRAL RESISTANCE REVIEW UPDATE

St. Louis, June 30, 2006 - Following the discovery by the Donald Danforth Plant Science Center that genetically modified virus-resistant varieties of cassava had lost resistance to the African Cassava Mosaic Virus, expert consultants were asked to review why and how the modified cassava had changed and to assess future plans. The committee of experts included Drs. Phil Needleman, chair, Ernie Jaworski, Ralph Quatrano, Steve Reiser, Eric Richards and Roy Vagelos; each expert brought important scientific perspectives to their task.

The group reviewed the data and concurred with the conclusions that resistance to African Cassava Mosaic Virus was achieved in cassava line Y-85, that the resistance was subsequently lost, and that methylation of the plants’ DNA had taken place.

In addition, the committee concluded that “the current plan for generating stable viral resistant plants is viable with a reasonable probability of success.” The committee reviewed the plans for going forward and made a number of recommendations, including the formation of a technical advisory committee, a quarterly review of the strategy and data, and improved record keeping.

The Danforth Center will be implementing these recommendations as we meet our commitment to address hunger and the nutritional needs of people in developing countries.