A paper was published at the end of August in the journal BRAIN that shows possibly that the first case of colorblindness has been cured. This comes after 13 years of apparent stagnation in gene therapy for CVD, ever since the Neitz Lab cured dichromacy in 2 squirrel monkeys in 2009.
The study involves 4 achromatic teenagers, 2 of each of the 2 main forms of achromatopsia, affecting either the CNGA3/CNGB3 proteins, which form part of the phototransduction pathway required for the cone photoreceptors to send signals to the brain.
The 4 subjects received gene therapy via a subretinal injection and after several months, fMRI in 2 of the subjects showed that the brain patterns excited by watching a spinning disk were very similar whether the scotopic (rod-driven) system or the photopic (cone-driven) system was active (depending on brightness). This indicated that the cones were now functional, which should at least alleviate some of the worst symptoms for achromats: photophobia and poor visual acuity.
Whether the subjects were able to interpret color was interestingly, out of the scope of the article. However, its also expected that the development of color vision would take several months and possibly be mild. Regardless, one older subject did claim that he had an easier time interpreting traffic lights. I’ll be making a video on these results soon.
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