The structure of the eyes of the zebra fish is almost identical to those of humans: a mosaic of light-sensitive cells. A recent study conducted by scientists in the FSU's Department of Biological Science and Program in Neuroscience (doctoral candidate Karen Alvarez-Delfin, postdoctoral fellow Ann Morris and Associate Professor James M. Fadool) showed the successful identification of the function of a gene called “tbx2b”. They have discovered that the gene mutation determines if the cells develop as rods (the photoreceptors responsible for dim-light vision) or as cones (the photoreceptors needed for colour vision). The newfound allele has been called “lor” for “lots of rods”, because the mutation results in too many rods formed and fewer ultraviolet cones than in the normal eye.
Described in a paper published in the Proceedings of the National Academy of Sciences (PNAS), the landmark study of retinal development in zebra fish larvae and the genetic switch it has identified should shed new light on the molecular mechanisms underlying that development and, consequently, provide needed insight on inherited retinal diseases in humans. Mr. James Fadool says that "our goal is to generate animal models of inherited diseases of the eye and retina to understand the progression of disease and find more effective treatments for blindness. We are excited about the mutation that has been identified because it is one of the few mutations in this clinically critical pathway that is responsible for cells developing into one photoreceptor subtype rather than another."
For more information:
http://www.sciencedaily.com/releases/2009/03/090324131548.htm
