Life Science and Medical News from Around the Globe
24 New Genes for Short-Sightedness Identified
An international team of scientists led by a group at King's College London has discovered 24 new genes that cause refractive errors and myopia (short-sightedness). Myopia is a major cause of blindness and visual impairment worldwide, and currently there is no cure. These findings, published online on February 10, 2013 in Nature Genetics, reveal genetic causes of the trait, which could lead to finding better treatments or ways of preventing the condition in the future. Thirty per cent of Western populations and up to 80 per cent of Asian people suffer from myopia. During visual development in childhood and adolescence the eye grows in length, but in myopes it grows too long, and light entering the eye is then focused in front of the retina rather than on it. This results in a blurred image. This refractive error can be corrected with glasses, contact lenses or surgery. However, the eye remains longer, the retina is thinner, and this may lead to retinal detachment, glaucoma, or macular degeneration, especially with higher degrees of myopia. Myopia is highly heritable, although up to now, little was known about the genetic background. To find the genes responsible, researchers from Europe, Asia, Australia, and the United States collaborated as the Consortium for Refraction and Myopia (CREAM). They analyzed genetic and refractive error data for over 45,000 people from 32 different studies, and found 24 new genes for this trait, and confirmed two previously reported genes. Interestingly, the genes did not show significant differences between the European and Asian groups, despite the higher prevelance among Asian people. The new genes include those which function in brain and eye tissue signalling, the structure of the eye, and eye development.