 The state of the art today from all the contributors we heard was that you can do these experiments, if you make the cells perhaps a bit more naive then you can get cells into the blastocyst, but the contributions that you see in post-implantation fetuses are very low. They’re not necessarily in all tissues, and the contributions are quite dispersed. So nobody showed us a very extensive contribution of human cells into an interspecies chimera (National Institutes of Health 2015).