Erin Blakemore at National Geographic
reports that 186 of the embryos developed into later-stage chimera embryos. In each later-stage pig embryo, about 1 in every 100,000 cells was human-derived.
Getting to even this earliest stage has been a long journey, reports Blakemore. Before moving on to human-pig chimeras, Belmonte and his colleagues first worked on mouse-rat chimeras. By using CRISPR/Cas9 gene editing (you may remember this from a previous topic - shadow) the researchers were able to remove the genes for certain organ formation from mouse blastocysts (a blastocyst is the cellular stage before the embryo).
They then injected rat stem cells into the blastocysts. They found that the stem cells filled the gaps and developed the missing organs, including a heart, pancreas and eye.

The work could eventually provide life-saving organs for those waiting on donor lists, but critics of the research believe that mixing humans and animals in any way crosses a line. In the United States, the National Institutes of Health has banned federal funding for human chimera research, though last August it signaled it might relax that ban for carefully monitored experiments.
Daniel Garry, a cardiologist who is leading a research project on chimeras at the University of Minnesota, tells Devlin he thinks the Salk experiment was performed ethically and responsibly. ''This is a significant advance that raises opportunities and ethical questions as well,'' he says, pointing out that many people's fears of half-man, half-beast chimeras are not really in the range of possibility in this study.

Things will get more complicated as the research progresses, however. ''At this point, we wanted to know whether human cells can contribute at all to address the 'yes or no' question,'' Belmonte says in a press release.
''Now that we know the answer is yes, our next challenge is to improve efficiency and guide the human cells into forming a particular organ in pigs.''

What do you think?

Is it okay as long as it is only 1 percent human? Is more than 50 percent too much?

Personally, I think it is monstrous. We'll create human abominations that exist solely for our own benefit, what kind of existence is that?

This is brilliant! Let's just use the wombs of live female animals for our convenience. Actually, that gives me a great idea..

Well. You can't have different moral boundaries for one and other...

Aww I love pregnant pigs

while i appreciate and realise how important organ donations are and how rare it is, how it means life or death, I can't feel comfortable or okay with this..

just because we can do something doesn't mean we should do it.

I also realise that my opinion would more than likely change or be ignored by myself should it mean the difference of life and death in myself or a loved one... I am human and we are all hypocritical to an extent...

but emotions aren't logical so I don't think this window should even be allowed to exist

My main problem is the fact that we will just be harvesting their organs, though I suspect chimeras of all kinds could be made for different purposes.
It all reminds me a little too much of Dr Moreau, I wonder if it will progress to the point where people can edit their own DNA..

Chimeran super soldiers, anybody? Imagine taking all the best stuff from the best predators and splicing it into a soldier? I'd be surprised if it wasn't already happening, or at least being researched.