David Goldstein of Duke University has predicted the mass use of pre-implantation genetic diagnosis (PGD) by many more families. This will be funnelled by three trends: our increasing knowledge of the genetic predisposition to particular maladies, the decreasing cost of such procedures and the regulatory framework within which such measures are carried out.
Dr Goldstein, however, expects its scope to widen significantly over the next ten years, as science starts to unlock more of the genetic factors that contribute to common conditions such as heart disease, type 2 diabetes, autism, schizophrenia and epilepsy.
It had been thought that much of the genetic influence over these diseases lay in common DNA variations with reasonably small effects, which would not be amenable to embryo screening. Recent research, however, has suggested that rarer variants with much larger effects on risk are actually more important. New technology for reading DNA will soon allow scientists to find many more of these variants with large effects, and also to screen for them in embryos.
There will be far more designer babies in 2020 than there are now, with strong consequences for cultural acceptance of the 'yuck factor'. Once a development is widespread, there is a demand for further potentialities, perhaps even enhancement.