In some parts of the world, that sex selection for boys - and it's usually for boys - reflects sex discrimination against girls, and it leads to very large imbalances - in China, in Korea, in India - in the population between boys and girls, a vast disproportion of boys to girls, and it reflects really this discriminatory attitude toward girls.

What intrigued me most was not the technology as such but the questions about the human goods, the fundamental human values and virtues that are raised by debates over biotechnology.

I think it would be a great tragedy to devote medical resources and genetic technological breakthroughs to purposes that are not to do with health or medicine, but instead are to do with satisfying the desires that are created by the consumer society.

The relief of suffering is a great good. The curing of illness and disease - these are great human goods. This is the mission of medicine.

My goal is first of all to promote a public debate about where markets serve the public good and where they don't belong. That's my first goal.

If we go too far down the road of choosing the genetic traits of children, my worry is that parenting will be less a kind of school for humility than it should be, and we will become too accustomed to regarding children as instruments of our ambition and of our desires.

I do think it is very important that the religious communities do try to bring their teachings and their insights to bear on the stem cell debate and on the debate about genetic engineering.