I don't think the controversy with gene selection is the actual selection of genes. Rather it is looking at the fetus and judging whether it is desirable or undesirable; if it has desirable genes, then you keep it. Conversely, if it has undesirable genes, it is discarded. I foresee this being applied to genetic disorders (dear god that is a dangerously vague term) and "violent", or "evil" genes. I'm serious about the last one. If (when) scientists discover what genetic factors influence violence and evil, there will most definitely be a push to congress for legislation allowing mandatory screening of all fetuses to ensure that they will not grow up into serial killers or rapists. What then would happened I don't know but probably abortion of the fetuses. And that's where the gene selection controversy would truly begin: the scrutiny of undesirable genes and the destruction of fetuses carrying those genes. It would be just like eugenics only this time around the reasoning would be, "we're saving lives."