Nature Biotechnology responds:

Although industry organizations, such as the Biotechnology Industry Organization (BIO), continue to support food crops for PMP and PMIP expression systems, we hold to our original view that they pose too many problems and nonfood crops are a better alternative (Nat. Biotechnol. 22, 133, 2004). In relation to Williams' concern over litigation, in our view, neighboring certified (e.g., GM free) organic growers in particular represent a litigation risk for farmers who elect to grow PMP/PMIP food crops in close proximity. Even if certified organic growers are comparatively scarce—only 73 organic growers are certified in North Carolina—their livelihood and certification status are under threat from PMP/PMIP crop admixture/introgression/hybridization events and thus they are likely to be especially vigilant for such events, more willing to file suit to protect their business interests and serve as rallying points for opposition.