Stem cells to cure blindness

Curing blindness is one of the hottest areas of stem cell research because eyes are unlikely to reject transplanted tissue and with an aging population, eyesight problems are a growing trend.

The US team behind this latest trial are already developing stem cell treatments for age-related macular degeneration, a condition affecting 30 million people worldwide.

But as with any stem cell therapy, the use of cells from human embryos is controversial.

Watch How We See Part 1: Eyes to find out more about how the eye works.