There is no reason to believe that once a sequence is put into the genetic code of the silkworm, that the code would spontaneously lose "the code." There is simply no record of it occurring, so I am wondering why this is a concern. Conversely Kim has on several occasions, stated that every strain known has been a viable transgenic. A transgenic that loses information couldn't be considered viable. Do you have knowledge of any strain, being nonviable? I am not saying it is impossible. I am saying it is highly improbable.
If anything, they will select what strains they go with, but it is particularly puzzling for me to see this...absent observation.
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