Animal Cloning and Its Applications in Agriculture and Medicine
Cloning of animals began in the 1950s with the cloning of amphibians for the purpose of determining the totipotency of animal cells and the irreversible nature of differentiated cells. Mammals were first cloned in 1986 from embryonic cells to study cell differentiation and to create clones for commercial use. Today mammals are cloned from body cells to study cellular reprogramming. Commercially, genetically engineered animal clones are used to produce pharmaceuticals and other products in milk, immune tolerant pig cells and organs for xenotransplantation research and cloned animals for agricultural purposes. Cloning of human embryos from a patient's own cells has been proposed as a way to produce therapy cells derived from embryonic stem cells which would be immune compatible with the patient after cell transplantation into the same patient. National debate is occurring over the issue of whether cloning of patient's cells should be used to produce cells for that patient's therapy.
Department of Animal Science, University of Wisconsin, Madison