Born this way? Society, sexuality and the search for the 'gay gene'

Are our sexual desires derived from our genes? Or can we make active choices about who we are sexually attracted to?

Over the past decade the idea that we are "born this way" - or that our sexuality is genetic - has become increasingly important. The mantra has become a political strategy, in particular for gay and lesbian communities, who see it as a way to protect themselves from discrimination. The movement has spawned blogs where people show pictures of their childhood to highlight the innate nature of their sexuality, and attacks on those who have questioned the theory.

But do the politics match the science?