Kosher pork and treife tomatoes
Wahrman, MZ. 2006.  BH 16:33-55. CELD ID 21475

Scientists are now able to manipulate the traits of plants and animals to produce genetically modified (GM) organisms with novel features. The successful production of GM fish, pigs, and other species leads to the speculation that genetic engineering could alter previously nonkosher species, transforming them into kosher species. In addition, might plants or animals genetically altered with DNA from nonkosher animals be rendered unkosher? Does genetic engineering provide a way to produce kosher pork and treife tomatoes? Would plants genetically engineered with animal DNA lose their neutral pareve status? IS it permissible under Jewish law to alter species and produce barnyards, ponds and fields filled with GM animals and plants? These questions will be addressed by considering rabbinic and talmudic perspectives on issues involved in genetic engineering. The principles of kilayim (forbidden mixtures); V'rappo yirappe ("Heal, he shall heal"); and tsaar baaley hayyim (concern for the suffering of animals) will be addressed.