Mutations in a particular gene may be the cause of a devastating condition that leads to babies being born without eyes.
Bilateral Anophthalmia is rare, affecting approximately one in every 100,000 births.
It happens when the foetus simply does not develop eyes in the normal way during the first 28 days of pregnancy.
The babies are born with empty eye sockets, and are often fitted with prosthetic eyes to allow normal facial development.
Researchers from the Human Genetics Unit in Edinburgh say that at least some cases may have their roots in a mutation of a gene called SOX2.
Their research, published in the journal Nature Genetics, will, say the scientists, reassure parents who fear that the blindness could have been their fault.
The geneticists from Edinburgh tested the SOX2 gene in children born with the condition and found mutations in many of them.
These genetic mistakes were not passed down from their parents - they are believed to have arisen spontaneously in either the egg or sperm involved.
The scientists believe that their finding could help doctors find ways to not only understand anophthalmia more fully, but also to help patients with other degenerative eye conditions, such as retinal and macular degeneration, cataracts and glaucoma.
Dr David Fitzpatrick, from the Human Genetics Unit, said: “The research demonstrates that SOX2 plays a critical role in eye development.
“We believe that other genes that directly interact with SOX2 may be mutated in children affected with similar and more common conditions.
“In addition to our quest to identify specific causes of these malformations our ultimate goal is to reduce the chance of them occurring in the first place.”
Revision date: July 6, 2011
Last revised: by Jorge P. Ribeiro, MD