Dolly the cloned sheep caused a media sensation. But after the hype subsided, what are the real issues? Why would it be wrong to clone human beings? What about possible medical uses of the technology, like cloning embryos for replacement body cells?
Cloning of human tissue is a very complex subject, and most of the 'cloning humans is wrong!' arguments seem to focus on just specific aspects, often ignoring medical fact in favor of a more sensational story.
For example, despite what is shown in science fiction movies, we can't clone a human being in a short amount of time, with the clone being an exact duplicate of the original, including memories, experiences, etc. If we could, that would definitely be a thorny ethical problem, but with our current cloning technology, scanning someone and having an exact clone duplicate pop out of a vat a couple hours later is not going to happen.
For a clone that is commiserate with our existing level of technology, we could, conceivably, take a cell sample from one person, implant a cloned egg into a surrogate mother, and then 9 months later we'd have a brand new baby whose only connection to the donor is genetic. The baby would grow up normally, develop their own personality, be their own person. With two provisions, I see this as no less ethical than artificial insemination. Those provisions would be:
1. The clone is recognized as a human being, with all the rights, responsibilities and privileges thereof.
2. Clones would need to have the same average lifespan as non-clones.
The first provision would seem to be obvious, but one of the recurring ethical problems brought up with cloning is the fear of creating a slave race of clones. Clearly, legal protections would have to be in place, otherwise you just know someone would try the 'clones are not really people' argument. And that's not even counting the fact that there is certainly going to be at least one argument from some of the more extreme religious groups that 'clones do not have souls'. There is a great danger of clones being a new class to oppress and discriminate against, and that should be nipped in the bud.
The second provision deals with the fact that current cloning techniques seem to result in shorter lifespans. Dolly, as I recall, aged rapidly. I've not kept up on current developments with this, but if it is still the case, cloning of humans should certainly wait until after we've solved this problem and cloned bodies live, on average, for as long as non-cloned bodies.
Now, as for cloning as a source of replacement organs, I think that this does show some promise. Here are three basic ways to do this:
1. Clone yourself. Let your clone grow up. Kill your clone and take their organs.
Clearly, this is an unethical, monstrous thing to do. it's also the main version people think of when cloning as a source of organ replacements is brought up. Numerous science fictions authors have dealt with this topic, such as the organages in Dave Duncan's novel "Strings", or Niven's organleggers in his Gil the Arm stories. I don't think anyone will disagree that this method is just plain wrong. Not only murder, but horribly pre-planned murder.
2. Clone yourself. Using technology not yet existent, prevent the brain from developing, ending up with a human body with no brain, just a brainstem. Harvest organs.
Less reprehensible than the first option, it is still a bit morbid. While there is no brain, no personality, no person within the body, the empty shell is still going to trigger certain 'that is a person' responses in people. Its best use, given the necessary technology, would be for a brain transplant for people whose bodies have been damaged beyond repair. Both the technology to prevent the brain from ever developing and the brain transplant technology are beyond our current reach, so I'd say that option 2 here is going to remain in the realm of fiction for some time yet.
3. Clone individual organs.
This really looks to be the best use of human cloning in our immediate future. We've had limited success already (human ear grown on the back of a mouse, etc), there's no 'person' involved, just a single organ, so very little uproar about the rights of the organ can be expected, and growing a single organ to maturity is probably going to be far simpler than figuring out how to speed-age an entire human being would be. The biggest difficulty I foresee is long-term stability, making certain that the cloned organs won't give out after only a year or to. Having to replace organs every few years would rapidly get prohibitively expensive.
I want to add that it is important to keep in mind that a monozygotic twin is also a pair of clones, because they are genetically identical. It is then important to realise that nobody is claiming one of the two is the "original" and the other "just a soulless copy". Of course, monozygotic twins are born around the same time. I understand if people object to this analogy in which a "twin" is made who is several years younger. Still, it's food for thought.
Of course we're speaking in terms of modern societies, but just as a note of interest, in many villages and tribal communities, twins are actually seen as signs of bad luck, and are horribly treated as a result. It can range from the twins becoming outcasts to even their murder.
And you forget that a lot of people don't really understand how twins work. Hell, I know two sisters who are twins and think that twins (of their type) aren't genetically identical.
Knowing this, it's really not all that far fetched to for people to say that clones have no souls.