| Some people have no plans to reproduce. Many women are quite willing to get with some ugly old geezer with money in order to get a cut of his money. Your hypothesis doesn't hold any water on the face of it, even before getting into much more complicated edge cases. I once saw a comment on a cystic fibrosis forum by a woman with CF who had a previous boyfriend with CF. CF causes significant reproductive problems, including that 97 percent of men with CF have vas deferens, so their ejaculate contains no live sperm. On top of that it is a homozygous recessive disorder, so it's very controversial for someone with CF to want biological children of their own since you have no hope of not passing on a defective gene. Two people with CF wanting a child together would be guaranteed to have a child with CF and it would almost certainly require medical intervention to happen at all. The CF community frequently has heated, emotional discussions about the morality of having more kids if your first child has CF, having biological kids at all if you have CF, etc. I also have read of people with certain disorders having intervention so they could have a biological child and select out the ones that got the bad genes because they knew how torturous the condition was and had no desire to do that to their own child. The ability to identify problematic genes via testing and the option to have certain kinds of fertility intervention is creating a whole slew of new questions. This complicated by the fact that genetic disorders profligate when they offer a survival advantage. This is the story behind Sickle Cell, which helps protect against malaria. It is also the reason CF is so much more common in Caucasian populations of European descent: Having only one of the genes doesn't give you a deadly condition and protects against an infection that rampantly killed people in Europe historically. So it is entirely possible that after designer babies become a thing and we remove too many "bad" genes from the gene pool, someday this will come back to bite us for some reason. |
>So it is entirely possible that after designer babies become a thing and we remove too many "bad" genes from the gene pool, someday this will come back to bite us for some reason.
Maybe, but unlikely. Those infections were a problem back then because we lived in huts and didn't have antibiotics or anything resembling modern medicine. A comment below says that this gene helps protect against cholera, for instance. Well cholera isn't a problem in places with proper sanitation, so this gene isn't really a help for people living in rich, industrialized nations. Sickle cell protecting against malaria might be useful to people living in malaria-prone areas still, but we do have immunizations against malaria these days, and in the future it's really not going to be a problem at all.
Finally, with "designer babies", presumably we'll be at the point where we'll just be able to genetically engineer ourselves to deal with any remaining environmental problems/diseases directly, instead of relying on some accidental mutation that gives us a little better resistance at a huge cost.