How we're using DNA tech to help farmers fight crop diseases

Nearly 800 million people worldwide depend on cassava for survival -- but this critical food source is under attack by entirely preventable viruses, says computational biologist and TED Senior Fellow Laura Boykin. She takes us to the farms in East Africa where she's working with a diverse team of scientists to help farmers keep their crops healthy using a portable DNA lab and mini supercomputer that can identify viruses in hours, instead of months.