Hollow friends,
There is a little article in todays hindu news paper which will bring a little 
hope in future.  The article is as follows:

Gene therapy could help blind people see again 
Washington (IANS): Researchers relied on gene therapy to restore vision to mice 
which suffered from degeneration of the light-sensing retinal rods and cones, a 
common cause of human blindness, because of lack of protein. 

"This is a proof of principle that someday we may be able to repair blindness 
in people with conditions like retinitis pigmentosa and macular degeneration," 
said Richard Masland, director of Cellular Neurobiology Lab at the 
Massachusetts General Hospital (MGH). 

"There are several limitations we need to overcome before we can begin clinical 
trials, but I'm optimistic that this work may someday make a big difference for 
people who otherwise would have no vision at all." 

The study was designed to investigate the effect of light-sensitive protein 
melanopsin in retinal ganglion cells of the eye. These specialised neurons 
receive light signals from the rods and cones and convey them to the brain via 
the optic nerve. 

Melanopsin is usually produced in a set of cells involved with establishing 
circadian rhythms but not with vision. The MGH team used the standard viral 
vector to deliver the gene encoding melanopsin throughout the retinas of mice 
whose rod and cone receptors had degenerated from lack of a crucial protein. 

Four weeks after delivery of the gene, melanopsin - normally produced in one 
percent of retinal ganglion cells - was found in about 10 percent of ganglion 
cells in the treated eyes but not in eyes that received a sham injection, 
according to a MGH press release. 

Examination of the melanopsin - expressing cells revealed that all responded to 
light, although the neuronal signal was delayed and persisted after the light 
signal had stopped, which is typical for a melanopsin - mediated signal. 

Two behavioural tests verified that the treated mice - which otherwise would 
have been essentially blind - had enough vision to find a darkened refuge in an 
otherwise brightly - lit area and to successfully learn that a light indicated 
a safe platform to which they could swim. 

"The same level of melanopsin expression in a human retina might allow someone 
who otherwise would be totally blind to read newspaper headlines, but the 
slowness of the response would be a problem," Masland said. 

These findings were published in Tuesday's edition of the Proceedings of the 
National Academy of Sciences. 

Yours G. Janardhana Naidu.
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