Scientists have found how to make eye cells sensitive to light, opening new ways to treat some forms of blindness.

Experts at Imperial College London teamed up with colleagues at the University of Manchester to study a protein, melanopsin.

Activating melanopsin in cells that do not normally use it made them sensitive to light, they told Nature.

The discovery might also help treat people who get depressed as the nights draw in.

The back of the human eye, called the retina, contains cells known as photoreceptors that interpret light levels to allow us to see.

Much human blindness is due to diseases of the retina, such as retinitis pigmentosa and macular degeneration, in which the photoreceptors are destroyed.

Currently there is no cure for such diseases, and once sight is lost it cannot be recovered.

Until recently, experts had thought there were only two types of photoreceptors – rods and cones.

But experiments on mice which have had their rods and cones destroyed, reveals that other cells in the retina also have some form of light response.

Scientists have suspected that melanopsin is important to all of these ‘light sensitive’ cells.

More here.