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00:13

We're talking biology with Dr. Ruth Tennen, and we're going to talk now about biotechnology.

00:19

Walk us through how scientists clone animals, 'cause it just sounds so cool.

00:26

Yes, it does sound cool. It's the Dolly idea, basically, that we've all hear about. Yep—the sheep.

00:33

And the basic process is called nuclear transplantation...is how most scientists would do it.

00:38

So you start off with an egg, and you empty out the DNA from that egg. So you end up with what's called an enucleated egg because there's no nucleus.

00:46

And then you take a differentiated cell, which basically means it's a skin cell or a heart cell. It's become something; it's a mature cell.

00:52

You take the DNA from that differentiated cell, and you insert it into that empty egg.

00:56

So basically you have turned that egg into essentially a fertilized egg.

01:00

You'd basically take that egg, you'd allow it to develop into an embryo...

01:04

...in a petri dish, and then you'd put it into a surrogate mom, so like a surrogate sheep mom...

01:08

...to allow it to develop. And then you'd be born with basically the genetically identical version of whatever organism you started with.

01:17

So why can't we do that with humans?

01:21

So there are definitely technical hurdles; I think the bigger hurdles are moral and ethical.

01:26

It's possible people are working on that stuff, but there are major international laws to prevent such things from happening right now.

01:32

And I think there's also always issues with who's going to have access to the technology...

01:37

...and it's really only going to be part of the population, and then does that cause inequalities and things like that. So there's a lot of ethical issues.

01:42

All right, so back into the real world: obviously there are good reasons to clone animals, and it's almost cloning and breeding...I guess a combined partnership...

01:53

How does that work? Give us some examples for what the state of the art is for cloning animals and breeding and kind of creating them.

01:59

There's a few reasons that people are cloning animals now.

02:02

So one is...so when we make animals models of disease...like if they want a mouse model of some human disease...

02:08

...it can take a long time to do that by breeding because you have to introduce multiple mutations...

02:12

...and you have to cross all the mice and everything.

02:15

If you had a mouse and you could just make a new version of that same mouse without having to do all that breeding, that would be a huge time saver.

02:20

So that's one thing. Definitely if you had some sort of livestock that had a particular trait you were interested in...

02:25

...it's easier probably to clone than to breed that.

02:27

There's a big market for bringing back extinct animals...and deceased pests, also.

02:39

So go back to the mice thing. What ethical issues arise when using animals for scientific experiments?

02:48

I think right now, we don't have a lot of other alternatives...

02:50

...so it's either test a drug on humans without testing it on animals...

02:54

...or you have to sacrifice some mice.

02:56

And there are tons of regulations about how the mice are treated. You have to submit a protocol to make sure that you're humanely treating the animals.

03:01

But all the time, there are people picketing outside of research universities saying, oh, you shouldn't be doing these experiments on mice.

03:10

Yeah, interesting ethical issue.

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