Vicar Philip

Good point about twins, Atom.

Do they have to be TWICE as good as non-identical siblings to get past the pearly gates?

Would quints have to be FIVE TIMES as good?

Talon

I mean think about it. What's the point?

Humans can reproduce without the large expense of this technology, so what is the benefit?


There are plenty of existing human children who are in need, why bother exploring this?

I do think in the future this scientific avenue may produce benefits, but only within the constraints of reproducing body part for the sake of helping the sick heal. By developing this technology we may in the future be able to "grow" genetically compatible replacement parts but, NOT for any other reason.


TALON

Viti

If they can supposedly clone a whole human, why can't they clone just organs for transplants (no ethical question and immediate benefit)? Is cloning parts more difficult than cloning the whole?

tronvillain

Well, that's really where all the work has been focused. The ability to clone a person has very little practical value (it would merely be another reproductive option), while cloning organs would be immensely valuable. Anyway, the only ethical concern I have about cloning is how reliable the process is - there is a significant potential for damage. Other than that, a clone is essentially (ignoring mitochondrial DNA) a younger identical twin. It is an interesting option to have available, but nothing to get excited about.

Demosthenes

it is a bit more difficult, since when you start cloning, the cells go off on their own genetic programs which invariably leads to a full grown organism. The researchers are figuring out how to manipulate the genetic programs to only give the desired organs as well as the necessary growth factors and support that will be necessary to clone organs. At an extreme, it's possible to clone a full body while preventing the brain from developing to serve as a transplant twin for people. But most find it repungant, not to mention the expenses necessary to keep the bodies alive.

lpetrich

Surprisingly, it is. If one wishes to clone some kidneys, one would have to find out which chemical signals command certain embryonic cells to start becoming a kidney -- chemical signals which embryos already know how to produce.

And knowledge of such chemical signaling may even make it possible to grow back a lost kidney, making a transplant unnecessary.

Exactly how this chemical signaling works has been a very murky subject, though there have been a few breakthroughs along the way, like the discovery of "Hox" genes. These are expressed in front-to-rear order, and help determine how each area of the body is to develop. They were first discovered in fruit flies, where Hox-gene mutations can cause antennae and mouthparts to develop like regular walking legs. Since then, they have been found in many other species. Here's a nice chart of fly and mouse Hox-gene expression areas.

AtomSmasher

If you think about it, why did we invent a car? People were doing fine with a horse weren't they,? If we would just spend more time helping the needy instead of wasting precious resources on "science" then we wouldn't have all these stupid problems we have today. We could live in a perfect utopia if it weren't for all the time lost on useless research into heart transplants, cures for cancer, anti-biotics. What a waste all that was, it could've have been better used in social programs, think of the children!.

In all seriousness, why would somebody be interested in this? How about couples that are infertile? If you want a baby but are somehow biologically incapable of producing one, wouldn't many people be interested in cloning? Most people would prefer to raise a child they are biologically related to as opposed to adopting. My selfish genes say "copy me!" every time I look at a potential mate, but after a quarrel with said mate my thinking brain says "hmmm... cloning..."

I suppose this is a common sense approach to cloning if you expect to get federal funding, or at least freedom to continue the research. Right now I can imagine the special interest groups are mobilizing for an assault on cloning research and all that can be hoped for is a compromise that falls short of an all out ban, but I expect some sort of legislation will result in new federal oversight of cloning research.

Demosthenes

I'm now curious to the psychological implications of having a cloned child instead of a convienient child. There's a line of argument suggesting that parents may consider their clones more valuable than regular children because the clones are so much closer to the parent in terms of genetics. Perhaps the parent would feel more connection to the clone since it can be reasonable expected that the clone would have similiar thinking and emotional patterns and offer a better chance of "immortality" than what a convienient child would offer.

It's entirely possible there'll be an entire new class of families consisting of cloned lines of the originals a'la David Brin's Glory Season

lpetrich

I hope I didn't go over everybody's head with my mention of Hox genes, but I did so to illustrate how it may someday be possible to grow replacement organs -- and why it is relatively difficult to grow a part instead of the whole.

Viti

Thanks for bearing with me guys...as some of you know I have a personal interest in this but am hopelessly ignorant of it

Okay, why can't they grow organs from existing organs (they are able to grow skin I believe). The liver is able to regenerate naturally, if it has this ability shouldn't we be able to use that to grow livers in a lab?