American researchers have published the most thorough description to date of gene expression in the human retina. And it comes with a few surprises.
The investigators at Massachusetts Eye and Ear and Harvard Medical School used a technique called RNA sequencing to demonstrate that the majority of the 20,000 genes in the human body are expressed in the retina. This was no real surprise to the scientific community, because the retina is a complex tissue with 60 types of cells.
The investigators were quite excited, however, to discover nearly 30,000 new exons and more than 100 potential new genes. Exons are the portions of the genome that are used to encode proteins or other genetic elements. Several thousand of the newly discovered exons appear to be used specifically in the retina.
These discoveries will help researchers to better understand how the retina works as well as how it is affected by various diseases, such as inherited degenerations, which result from genetic mutations or errors. While more than 200 genes related to retinal degenerative disease have been identified, scientists have yet to find the cause of disease for up to half of the patients with such disorders. The newly identified exons in the retina may change all that.
Sources:
http://www.sciencedaily.com/releases/2013/07/130718130458.htm
