Understanding ‘Chimeras’ And How They Might Save Lives

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The subject of both increasing scrutiny and increasing controversy, “chimeras” are the latest difficult topic scientists are grappling with. But what are they? Why are they being developed? And how will it affect us in the long term?

Here’s what you need to know:

What Is A ‘Chimera?’

In scientific terms, a chimera is an animal with some DNA from another animal spliced into it. The chimeras you’re hearing so much about in the news are controversial because scientists are inserting human DNA into pigs, creating “pig-human” hybrids. But this isn’t some sort of cheesy SF movie scenario; in fact you’d likely be unable to tell a chimera from a typical pig by looking at it. Scientists have no interest in making a nightmare.

Why Are Chimeras Being Made?

The world is struggling with an organ problem. Organ transplant lists are growing constantly, but doctors can’t locate enough organs to transplant. So, the theory goes that if you splice human stem cells into pig DNA, after removing the genetic code that grows a specific organ, the piglet will have a human pancreas we can use for transplantation. This is, however, only a theory, so scientists at the University of California, Davis, are testing it to see if it’ll work.

Couldn’t The Pig Become A… Kind Of… Person?

Probably not, but the research team is taking no chances. The tests will terminate the pig embryos after 28 days to see if any human cells have been created. They’ve tested this before, without creating the “genetic niche” that removing the section of DNA causes, and found human cells, but they had to compete with pig cells. They’re also closely monitoring the brain; if, somehow, the embryos are developing human-like brains, they’ll be terminated immediately.

Are There Ethics Concerns?

There absolutely are, and everyone involved is struggling with them. Leaving aside for the moment the animal rights end of things — although needless to say they’re not fans — the idea of creating any sort of animal-human hybrid doesn’t sit well with most people, even the scientists conducting the study. Nobody longs for super-intelligent pigs or cats the size of toddlers roaming the Earth. Particularly because they would serve no useful scientific purpose, and the potential for suffering on the part of the animal is vast.

Beyond that, there are some major questions about the quality of the organs and whether or not they would make livestock diseases transferable to humans. Even if we do create a human organ in an otherwise normal pig, that doesn’t mean we’re out of the woods. It may not be a good transplant choice for a multitude of medical reasons. And that’s not even getting into the religious objections that may result, or the personal distaste a patient might feel. It might be scientifically possible and yet ethically insurmountable for many people.

So Why Do It?

Very simple: We need the organs. Even if we don’t use them for transplantation, they can still be a source of tissue to be used for medical experiments such as drug studies that don’t put humans at risk. It’s true that chimeras are controversial and that’s unlikely to change any time soon. But there’s simply too much at stake to not see where this science can take us, and it’s better it be done in a scientifically rigorous environment concerned with ethics.

Also, it’s worth noting that this may not pan out. Still, it’s better to know than to leave human lives on the table.

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