What is the effect on the human genome over time of saving unhealthy children?

[smiling_bandit]

Your average Afgani fighter wears the same style jacket shirt and trousers year round. The soviets on the other hand were stopped by the cold weather in Afganistan. Is this because the Afgani people are better acclimated to the climate or is it because with their generaly low level of technology only the strong can survive there?

B.S. Russia had only been modernized for, at most, three generations. A hundred years back they were all peasant farmers, pretty much.

Moreover, your all missing one important fact: people with nasty genetic diseases tend to breed less often and have fewer children anyway.

[DSeid]

I think that edwino’s point has been lost on some. “Fitness” is self-defining. If the genes are being reproduced then they are fit.

Let us take genes for bad vision as an example.

Thousands of years ago, that would have been significantly “unfit”, poor vision means poor hunting and/or gathering, means less ability to survive and/or attract mates and get children to survive long enough to reproduce.

Now, with wide availibility of corrective glasses, poor eyesight is neutral on genetic fitness. In fact, individual genetic fitness is actually served best by some irresponsibilty and reproducing willy nilly even though that stresses out the species and planet as a whole. But some things are more important than genetic fitness.

[edwino]

Exactly DSeid. We have plenty of examples from the animal kingdom where the “strongest” characteristics are selected against. The peacock’s tail, the red of the male cardinal, giant moose antlers, and the size of the human cranium all decrease an animal’s raw survivability, if you were to make up some measurement of that. Yet the genes encoding all of these things are quite fit – usually because of sexual preference but there are other reasons as well.

The hardiest creatures on the planet are not Afghanis – they are the cockroaches, fruit flies, kangaroo mice, thermophilic and halophilic bacteria, Staphylococcus and enteric bacteria, etc. The reason the human has been able to develop such a large brain without giant claws, teeth, or tusks for protection is probably because most of our evolution took place in a fertile, energy rich area where raw survival was not much of an issue.

[BURNER]

originaly by; John Mace

You have to be careful about extrapolations. You cannot take an isolated issue (like a few “deformed” individuals) and extrapolate out to infinity assuming that nothing else changes. For example, if there were a “deformity” that required someone to be cared for constantly, and if that deformity occured in, say, 75% of the population, those people would start dying off since there wouldn’t be enough people, as you said, to take care of them. The population would tend to stabilize at some level below 100% occurance.

Think of the balance in nature of predator and prey. You cannot affect one population w/o affecting the other.

But let’s just say that you were correct. That the gene pool was being destroyed by recessive genes. What would you propose? Eugenics?

I drew a possible conclusion based on what I know about genetics. If people with physical and mental defects reproduce, then their genes are passed on into the next generation. They may not manifest themselves, but they are still there. Thats why they ask for your whole family history with certain illneses, like heart disease. If all of your grandfathers on one side of the family dropped dead of a heart attack by age 50 the chance is there for the same to happen to you. The genes may never manifest, but they are still there. That is why there are certain illnesses that are more common in certain ethnic groups, like sickle cell anemia. This is all just a big “what if” though because I cant tell what the future will be. It is just something that I see as a possibility. I am not qualified to make a call about eugenics. My only opinon would be that nature should be allowed to take its course. If the child can survive outside of the womb despite any problems it might have, then who an I to say destroy it. I think it is wrong to force it to live if it needs 2 dozen machines to keeps it functioning.

I want to address the balance of nature comment as well. Humans have no balance any more. We have killed or contained almost everything that can kill us. Most diseases can be cured, even AIDS can be stalled for years with the use of drugs. Animals that prey on us are killed before they can get more than 1 or 2 people. Our only predator left is age. From what I hear scientist are looking for a cure for old age as well. Maybe one day we will get out wish and no one will die any more. I hope they enjoy the over crowding.

[John_Mace]

Burner:

How about if the baby needs 23 machines to survive? 15? 5? 2? Any number you pick is going to be arbitrary. I’ve known people who’ve had 2-3 month premature babies that BARELY survived with all kinds of technology and who turned out perfectly normal in the end.

I know what you’re getting at, and doctors agonize over “quality of life” issues all the time. The problem is that we just aren’t clarvoyant enough to know with great certaintity in many cases what the quality of life will actually be like. Infants may be fragile, but they also can bounce back better in some cases than adults can from things like brain damage, etc.