The problem with that though, is loss of genetic diversity.
Not all disease causing mutations are wholly bad, and needing to be removed.
It sounds callous as fuck, but the BEST solution is to let nature and natural selection do their things. That means: Stop intervening with genetically based diseases that are terminal.
The path of human evolution is difficult, if not impossible to predict. When you start choosing how the species will evolve, (and in so doing, ignoring the evolution happening in the environment), humans stop evolving in concert with the environment, and become less genetically fit over time. (That is to say, the environment gets a leg-up on the humans, who think they know better than nature, and are doing their own thing...)
This is of course, VERY unpopular as a position-- It means letting little timmy with XYZ lethal syndrome die horribly (as nature intends), even if there is a life-saving treatment that would allow him to live on drugs for the rest of his life.
An example of why we need to leave deleterious mutations, is sickle-cell anemia. It makes people basically immune to malaria. It also causes persistent anemia. The mutation allows more human genome to be preserved (It requires homogenous alleles to cause the anemia, but only requires heterogenous expression to confer STRONG resistance to malaria) in the face of a very deadly contagious disease, and thus helps the human genepool.
Such mutations lead to subsequent mutations; The anemia causing gene may allow humans to survive long enough for malaria to mutate, at which time the detrimental effects of the anemia gene would cause selective bias against-- OR-- it may serve as the basis for further mutations of that gene, restoring function later, but keeping the immunity.
Since we can't predict which way the genome will be selected for, because we cant predict which way the pathogen will evolve, removing the "defect" is very unwise.
Further, we can't predict which mutations currently exist that might lead to protection later-- Take for instance the CCR5-delta32 mutation found in many people of european descent. This mutation causes loss of function on several cellular receptors, and was selected for as a result of repeated exposure to the black death. This mutation also confers a profound resistance to one of the more common forms of HIV-- If we had chosen to eliminate this "defect" in our germ line, HIV would have been far more catastrophic in europe.
Again, the "Best" solution is to allow people to die from genetic diseases, without trying to intervene.
Allowing little timmy to die today, can save the world tomorrow.