In an article appearing online in the American Journal of Human Genetics a Ben-Gurion University of the Negev research group led by Professor Ohad Birk has identified a gene whose defect specifically causes myopia or nearsightedness. "We are finally beginning to understand at a molecular level why nearsightedness occurs," Professor Birk relayed. The discovery was a group effort at BGU's Morris Kahn Laboratory of Human Genetics at the National Institute for Biotechnology in the Negev and the Dayan Clinical Genetics Wing at Soroka University Medical Center.
Nearsightedness is the most common human eye disorder and is mostly a hereditary trait. Aside from being a significant public health concern, nearsightedness also leads to a higher incidence of other secondary eye disorders, such as retinal detachment, macular degeneration, as well as early onset glaucoma and cataracts. Despite decades of intensive research, the specific genes whose defects lead to nearsightedness have remained elusive. The defective gene was identified in a thorough study of severe early-onset myopia that is common in a specific Bedouin tribe in southern Israel. The gene encodes an enzyme that is essential for the final modification of collagen in the eye. In the absence of the active form of this enzyme, aberrant collagen is formed, causing the human eyeball to be longer than normal. As a consequence, light beams entering the eyeball focus in front of the retina rather than on the retina itself and myopia emerges.