Abstract
Genetically engineered pigs with multiple gene deletions and insertions are predicted to extend porcine to human xenograft survival. Several genes have been successfully knocked out and inserted, yet more have failed to produce viable animals for unexplained reasons. The effects of gene editing on cellular homeostasis may be the cause of reduced embryo fitness, failed pregnancies, or poor piglet viability. The elements of cellular dysfunction such as endoplasmic reticulum stress and oxidative stress induced by gene editing may additively affect the quality of genetically engineered cells to be used for cloning. Evaluating the impact of each gene edit on cellular fitness for cloning will allow researchers to maintain the cellular homeostasis of engineered cells that were validated as candidates for cloning and the production of porcine organ donors.