Re: Progress
There are a slew of diseases for which the heterozygote confers some hypothetical sort of advantage.
You picked one (sickle cell , a class of beta-globin mutations). There are many similar diseases within the beta-globin gene, depending on how far down the protein chain the mutations occur. In the interests of being precise, this can lead to truncations as well....
The heterozygotes manufacture a proportion of mis-shaped blood cells (the allele ratios of the genes), that can disrupt the malarial life cycle, thus giving the body a fighting chance.
The homozygote has an awful, and possible very short life, as all the blood cells are mis-shaped inhibiting cellular respiration and premature clotting.
There is no shortage of *breathtaking* awful medical conditions to worry about "subtle advantages".
This is also a very large number of foetuses that are arborted after a few cellular divisions, due to inherent flaws.
The only way to be sure is to do the science and apply some rational decisions for which deserve to be fixed at all costs.
There are no "convential" treatments when it comes to genetic therapies.
This is just another tool towards that goal.
P.