Human-pig embryos Q&A: how would 'chimeras' make transplant organs?

Scientists have successfully created part-pig, part-human embryos. How have they done this, and could viable human organs really be grown this way?

Scientists at the University of California, Davis, are hoping to find a way of growing human organs inside pigs, which can then be transplanted into humans. The technique involves altering the genetic makeup of the pigs so that they do not develop a pancreas and then injecting human cells that will go on to make replacement organs inside the animals.