It is wonderful to have tests that can tell a mother and father if their child will have problems. Many of these problems can be taken care of in utero. And if there is a severe condition, abortion is always an option. However, we need to educate people against selecting only certain type of children or even selecting by sex.
With the technological advances we have made, it does not make sense to still leave up to chance things that can be quickly, easily, and reliably determined. Since it is now possible for parents to screen for healthier offspring, it only makes sense that they should screen for healthier offspring. Since parents can know, it is their responsibility to know if their potential children are going to be unhealthy or not, and to make the decision to have children or not accordingly.