My biggest issue is the patent laws. You shouldn't be able to claim living things as intellectual property.
If you can claim living things as intellectual property, then the onus to control their propagation is on you. If a farmer did not intentionally plant your product, but your genetic property ends up in their field, they should be able to sue you and not the other way around.
My secondary issue is largely surrounding the trustworthiness of corporations in general. Genetic Modification is a powerful tool. Whether it is good or bad depends on how the people with ability to use that tool choose to use it.
I would honestly feel better about it if the government was operating and funding research and development based around objectives determined to be in the interest of the public good, with the products of said research released to the public domain.
