I have a related question:
If a child is born with a disease or condidtion which everyone knows is going to kill them when they're older is it wrong to let them die earlier?
the reaction now is to do all you can for the child to keep it alive, when if it had been born 100 years ago it would not have lived long. would it be wrong for the parents to decide that it was not worth the investment and struggle of keeping it alive?

the same question kind of applies to any technology that's developed to let parents find out fairly early whethere there was omething wrong with their child. would it be wrong to abort a pregnancy if you knew that the child was going to have some terrible illness?