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← Sky-blue-pink. A colour never before seen?

Nastika's Avatar Jump to comment 10 by Nastika

There is a recent paper in Nature: Mancuso et al. 2009: Gene therapy for red–green colour blindness in adult primates (doi:10.1038/nature08401 and http://www.nature.com/nature/journal/v461/n7265/full/nature08401.html) that sheds light (ahem) on the question:

It describes how an L-opsin carrying recombinant adeno-associated virus was injected into the retinas of adult squirrel monkeys with red-green colour blindness. These dichromatic monkeys could only make out blue and yellow hues whereas their trichromatic counterparts could make out blue, yellow, red and green.

The dichromatic (colour blind) monkeys carried out a test before treatment that measured who well they could see colour hues. As expected they were unable to distinguish between blue-green and red-violet hues.

Five months after treatment, the dichromatic monkeys were found to have trichromatic vision after carrying out the same test.

The authors conclude that there was no rewiring of neural circuitry in restoring trichromatic vision based upon the fact that the new colour vision appeared at the same time as high levels of transgene expression. They were clearly unable to determine whether the monkeys experience new internal sensations of red and green but they go on to mention that evolution acts on behaviour not on internalised experiences so that their therapy repeated what happened during the evolution of trichromacy in primates.

Sat, 12 Jun 2010 12:55:22 UTC | #479589