Thank you for your inquiry about genetically modified foods.
Kashrut is an ancient system for bringing holiness to our eating. As a system of reverence and discipline, it links Jews across the ages and around the world, instills a sense of the sanctity of life, and teaches us to elevate our lives in the service of God and God's creation.
While kashrut stands for many things, one thing that it does not embody is health. One can keep strictly kosher and eat poorly. (Hot fudge sundaes, for example are quite kosher, alas!) The genetic modification of food does not automatically change the kosher status of a food.
As to the environmental and moral issues raised by modifying the genetic background of food products, that is indeed an issue that Judaism ought to percolate in the light of Torah, but not as an issue of kashrut. There are many rich teachings about how we are to live with the rest of creation and how we are to care for God's creation. Those sources will indeed direct how we intervene in other natural unfoldings.