[xenobioticants]

Those things are equivalent, only in the first case you do it retroactively instead of proactively. Hell, if gene modification becomes advanced enough you could even let people with hereditary diseases just reproduce and 'edit' the created embryo so it doesn't have said hereditary genes.

[lostlogin]

It's not quite like this but people with Huntingdon's can have embryos tested and healthy ones implanted so that their kids don't have Huntingdon's. This Nature article describes the process in 2002. www.nature.com/ejhg/journal/v10/n10/full/5200865a.html