starship earth

Originally posted by apathist
We shouldn't for example eliminate genetic disease by genetic manipulation?

Of course we shouldn't reject the elimination of genetic disease by genetic manipulation. But, judging from the irrational crazed moronic mentality I have seen in some, I bet some morons would shout "Eugenics" and "Nazi" and "racist" and "gas chamber", without explaining what one has to do with the other, just for suggesting such a sensible good thing even though genetic modification of people with genetic diseases to cure them would not only cure white people but would also cure black people who would just as desperately want to be cured. And it isn't as if anyone will be forced to be genetically modified; if someone rejects the treatment on religious grounds or for whatever the reason for his rejection, he would be just left untreated without GM treatment to suffer whatever consequences; his choice; no problem.

Originally posted by apathist
We shouldn't for example eliminate genetic disease by genetic manipulation?

The classic example is sickle cell anaemia, a disease which has the benefit of providing resistance to malaria. Cure the one and you may fall victim to the other. So the lesson is: be careful what disease you eradicate, because the ones left may have higher mortality rates than the first one.

Originally posted by moonbus
The classic example is sickle cell anaemia, a disease which has the benefit of providing resistance to malaria. Cure the one and you may fall victim to the other. So the lesson is: be careful what disease you eradicate, because the ones left may have higher mortality rates than the first one.

If we continue to modify our genetics on purpose, at what point would humans have evolved into something else? I think that's an interesting question.

Originally posted by moonbus
The classic example is sickle cell anaemia, a disease which has the benefit of providing resistance to malaria. Cure the one and you may fall victim to the other. So the lesson is: be careful what disease you eradicate, because the ones left may have higher mortality rates than the first one.

Of course we must be careful. But ultimately there are many genetic diseases which we should, without question, cure. This includes sickle cell anaemia at least in regions where malaria is not endemic. Even where it is endemic, the increased risk may be worth it.

Originally posted by apathist
If we continue to modify our genetics on purpose, at what point would humans have evolved into something else? I think that's an interesting question.

The accepted criterion for the splitting off of a new species is inability to cross breed. That is, if what comes after us can no longer mate with us and produce fertile offspring, then what comes after us is a new species. Speciation is not a single-event issue; there is likely to be a period of overlap during which some individuals can mate with some other individuals and still produce fertile offspring, but a few generations later, this is no longer the case. Speciation is ascertained only in retrospect.

Originally posted by apathist
If we continue to modify our genetics on purpose, at what point would humans have evolved into something else? I think that's an interesting question.

As with anything in biology there really aren't any clear cut boundaries and any boundary we label is largely our own label and not a clear property of nature. Species are like that. They are our own classification system not a real property of life.
From a purely technical stand point we 'evolve into something else' every single generation. From another perspective, one could claim that a 'stage' in evolution has not taken place until a particular new gene has spread throughout the population. I wonder how many generations that will take in humans. Or current common ancestor is many thousands of years ago. There are people in different parts of the world who share no common ancestors for thousands of years and thus you must either claim we haven't evolved in thousands of years or we have evolved in two or more directions.

Originally posted by apathist
If we continue to modify our genetics on purpose, at what point would humans have evolved into something else? I think that's an interesting question.

Humans are continuously evolving into something else, whether on purpose or not.

Originally posted by moonbus
The accepted criterion for the splitting off of a new species is inability to cross breed. That is, if what comes after us can no longer mate with us and produce fertile offspring, then what comes after us is a new species. Speciation is not a single-event issue; there is likely to be a period of overlap during which some individuals can mate with some other in ...[text shortened]... a few generations later, this is no longer the case. Speciation is ascertained only in retrospect.

Ah. But as we become master of intentional genetic manipulation, that definition seems problematic.

Originally posted by KazetNagorra
Humans are continuously evolving into something else, whether on purpose or not.

Of course. Except that with intentional selection, we could actually prevent random mutations!

Originally posted by apathist
Of course. Except that with intentional selection, we could actually prevent random mutations!

No, we cannot.
We can correct particular mutations, but short of all out cloning we cannot do much about the vast majority of mutations. And even with cloning there will be some.

Originally posted by apathist
Of course. Except that with intentional selection, we could actually prevent random mutations!

You can't really prevent them, although one should be able to cure some genetic diseases, in principle.

Originally posted by apathist
If we continue to modify our genetics on purpose, at what point would humans have evolved into something else? I think that's an interesting question.

Allogeneic bone marrow transplants are already common procedures for curing cancers and blood system disorders. The result of a successful transplant is essentially a chimeric human. In a heritable disease context, all the cells outside the blood system will still contain the mutation, while the blood system is comprised of cells from another person. So the donor cell DNA is not heritable.

With all the cool new gene editing tools, it is now possible to take a patient, remove the stem cells from his bone marrow, correct the mutation, and re-transplant those cells back into the patient. This technique prevents complications from graft versus host disease, and is also not heritable.

For ethical reasons, I think a lot of the recent advances in human genetic engineering have avoided manipulation of heritable DNA, and instead focused on genetic modification directly in the system affected by disease. I think researchers will be able to continue down this road for quite awhile before it becomes necessary to manipulate germ line DNA. I agree that it will be very interesting to see what happens if/when that threshold is crossed.

Originally posted by wildgrass
Allogeneic bone marrow transplants are already common procedures for curing cancers and blood system disorders. The result of a successful transplant is essentially a chimeric human. In a heritable disease context, all the cells outside the blood system will still contain the mutation, while the blood system is comprised of cells from another person. So th ...[text shortened]... I agree that it will be very interesting to see what happens if/when that threshold is crossed.

Neil Degrasse Tyson said in an interview, "there is only a very small percentage of genes that separate us from apes. What I worry about is suppose we come across someone whose small change in genes puts them as far ahead of us as we are of apes''.

I guess he is saying it might not be a huge jump in genes to make us superhuman, and of course we can't know what gene mods, if any, would do that.

Originally posted by sonhouse
I guess he is saying it might not be a huge jump in genes to make us superhuman, and of course we can't know what gene mods, if any, would do that.

Genetics is so complicated that it will be a very long time before we can effectively invent new genes. What we can do is:
1. Fix damaged genes.
2. Copy genes from people with desirable traits.
3. Get genes from other species.

The last one has great potential but also possible pitfalls. For example, we got add a gene that allows our cells to manufacture a particular vitamin whose shortage in food sources currently cause many deaths or disease. This sounds great at first, but it is almost impossible to know in advance what this change would do. Our bodies are not designed to handle it, so it may cause more problems than it solves. How do we test it? If tested on new humans then there is an issue of consent.

We could also give ourselves better vision, but it might also have downsides.

Originally posted by twhitehead
No, we cannot.
We can correct particular mutations, but short of all out cloning we cannot do much about the vast majority of mutations. And even with cloning there will be some.

I said we could. Future. As powerful as your brain is, imagination is not your strong suit. I wish I had your understanding of reality, so I could offer some corrections. I'd expect the same treatment in return.