According to the BBC News, researchers from Newcastle University and Kings College, London, have asked the Human Fertilisation and Embryology Authority for permission to create embryos by fusing human DNA with cow eggs. These chimeric eggs would be used for embryonic stem cell research, destroyed after the stem cells are extracted. This appears to be their way around the short supply of human eggs to use in embryonic stem cell research, but the thing is, these would be chimeric embryos; they're saying 99.9% human. Does that other .1% matter?
While I can understand the idea of test runs before moving on to more valuable (rare) human eggs, I'm not necessarily convinced that this sort of test run needs to be done. We know the technology works, we know how to use it - what, entirely, is the point?
(Then again, I'm not convinced of the opposition argument by Calum MacKellar, of the Scottish Council on Human Bioethics, which basically says there is a line of separation between humans and animals, and to blur that line undermines the distinctions between the species, as well as running the risk of underming human dignity.)