This episode of BBC World’s Discovery podcast looks at the science which is already allowing parents to choose those embryoes least likely to develop diseases later in life. At first these techniques seem like powerful tools to put in the hands of would-be parents, but since any genetic assessment can only give probability, not certainty, it has the potential to create agonizing choices. And the programme also looks at India, where pale skin is becoming increasingly desirable, especially for girls, and asks if legislation should stop parents from rejecting embryoes for aesthetic rather than medical reasons.

Listen to the episode (streaming audio hosted by the BBC)