Dominic Lawson asks the environmentalist Mark Lynas why he now supports genetically modified crops and what the reaction has been from his former colleagues.

In this series Dominic Lawson interviews people who have changed their mind on controversial matters.

This week he asks the environmentalist Mark Lynas, who was once a prominent figure in direct actions to destroy genetically modified crops, why he now advocates for GM technology and what the reaction has been from his former allies.

Producer: Martin Rosenbaum.