Therapy Fixes Color Blindness in Monkeys

[sandy]

Monkeys once color-blind can now see the world in full color thanks to gene therapy. The results demonstrate the potential for such methods to eventually cure human vision disorders, from color blindness to possibly other conditions leading to full blindness.

The primate patients, named Dalton and Sam, are two adult, male squirrel monkeys that were red-green color-blind since birth - a condition that similarly affects human males more than females. Five months after researchers injected human genes into the monkeys' eyes, the duo could see red as if they had always had this ability. Since human genes were used and the monkeys' eyes and brains are similar to ours, at least in terms of color vision, the researchers hope the same procedure could work in humans.

http://news.yahoo.com/s/livescience/20090916/sc_livescience/therapyfixescolorblindnessinmonkeys

Most excellent, no?

 

[Enmos]

I call bullshit.
And red-green colorblind people see red fine.

 

[Hercules Rockefeller]

No, it’s real. I haven't read the Yahoo news piece, nor will I. Don’t ever get your science news from Yahoo (or any other mass media lowest-common-denominator news source).

Here is a better source: ScienceDaily. I like SD as it often sources directly from the relevant university press release.

...or even better: Nature News

...or better again, the actual publication in Nature: Mancuso, K. et al. Nature advanced online publication, doi:10.1038/nature08401 (2009).

There have been a number of gene or cellular therapy attempts of one type or another in the eye. Along with bone marrow it has been the only tissue/organ that has seen any reasonable success with gene therapy. People have introduced new genes (as per the example above) to restore gene function, introduced siRNA to block gene function (eg. as a treatment for macular degeneration), and introduced stem cells to replace retinal degeneration/damage.

The eye offers the amazing opportunity to access the brain in a relatively non-invasive way. The back of the eye (the retina) is, in a fashion, the most rostro-anterior part of the brain. There are neurons there that have direct axonal connection to the optic tectum (maybe via interneurons, I’m not sure), and all you have to do to expose them to gene therapy vectors is to inject the vectors into the eyeball.

 

[Asguard]

HR why use the eye when you can use the nose?
as far as i know the orfactory senses arnt concidered a TRUE sensory organ at all (in the way the eyes, the skin, taste buds and ears are) but rather an extention of the brain itself

 

[Hercules Rockefeller]

Well, if you want to try to correct a vision-related genetic defect, I’m not sure there’s much point introducing your gene therapy vectors into olfactory sensory neurons at the top of the nasal epithelium.

 

[Asguard]

i didnt mean to fix eyes, i was responding to your point that the easiest way to get access to the brain is through the eyes

 

[Orleander]

I call bullshit.
And red-green colorblind people see red fine.

My Dad couldn't. :shrug: Was he a rarity?

 

[sandy]

Most red-greed color blind peeps I know can't see fine, either.

 

[Enmos]

Most red-greed color blind peeps I know can't see fine, either.

They can't see fine at all?

 

[Enmos]

My Dad couldn't. :shrug: Was he a rarity?

He couldn't see red?
The way it works with me is I can see all colors fine, I just somehow confuse them. I see them right but I can't always differentiate.. does that make sense? It's hard to explain.

 

[sandy]

That's what I meant. They confuse colors.

 

[Orleander]

How would a person who doesn't see colour the way others do, know what red (that the others see) looks like?

 

[Enmos]

How would a person who doesn't see colour the way others do, know what red (that the others see) looks like?

How does any person know how another person sees whatever color.

 

[Orleander]

are you serious???

Because we all agree on the colour of a certain object. A colour blind person wouldn't. How would they then know what the red I see is?

 

[sandy]

Good questions.

 

[Asguard]

orleander it doesnt matter what colour you actually see, if what i see as red you see as green doesnt matter. What is important and whats missing in colour blindness is the ability to DISTINGUISH one colour from the other, for instance red green (most common) colour blind people see both red and green as a sort of brown, now wether that brown objectivly looks "green" to them subjectivily it doesnt matter.

 

[Enmos]

are you serious???

Because we all agree on the colour of a certain object. A colour blind person wouldn't. How would they then know what the red I see is?

You could very well see the color green as another person sees the color green as you see the color purple. You both call it green.. so how would you ever know?

 

[sandy]

Now I'm really confused.

 

[Enmos]

Now I'm really confused.

I worded it badly I guess.

You and another person are looking at a colored square.

You see it like this:

You declare the square to be green.

The other person might see this:

The other person also declares that the square is green.

How will you ever know whether or not the other person sees what you call the color green exactly as you see it?
And, really, it doesn't matter what you actually see if you are calling it the same color, right?
Besides, it cannot be known anyway.

 

[Hercules Rockefeller]

The wikipedia entry on colour blindness has some figures that demonstrate what the colours of the rainbow look like to people with various forms of colour blindness.

http://en.wikipedia.org/wiki/Color_blindness