Light passing through the body and into the womb could play an increasingly important role in the developing eye thanks to new research.
A US study has discovered that tiny quantities of light can be used to control blood vessel growth in the eye.
Researchers from University of California and Cincinnati Children's Hospital Medical Center looked at the impact on blood vessel development in the offspring of mice who spent their pregnancy in varying degrees of darkness and found those in complete darkness had babies with altered eye development.
Study lead Prof Richard Lang admitted the findings were a "huge surprise" and added: "It's not something subtle here, it's a major effect on the way the retina develops that requires light going through the body."
The researchers hope their findings may aid understanding of human diseases of the eye, as many are down to blood vessels.
Some babies born prematurely develop "retinopathy of prematurity", when the blood vessels in the eye grow abnormally resulting in damage to the retina and a loss of vision.
"In retinopathy of prematurity there is overgrowth of blood vessels and that's what you see in these mice," added Prof Lang.
The study, published in the journal Nature, also shows that light activates a protein, melanopsin, which also has a role in regulating the body clock, and is present in people.
The critical period for retinopathy was around 16 days, which corresponds to the first trimester for women but further research is required to identify whether the same processes take place in people or other animals.
Posted 17/01/2013 by email@example.com