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Japanese Scientists Create Artificial Eyeballs
MikeyMars writes: "CNN is reporting that Japanese scientists have grown artificial eyeballs [cnn.com] for tadpoles. This is the first time in the world something like this has been accomplished. 'Since the basics of body-making is common to that of human beings, I think this might help enable people to regain vision in the future,' Asashima was quoted as saying."
Got to wonder how long until this ingredient makes it to Iron Chef....
Papa Legba come and open the gate
Yes, but if they get this working can you imagine the great advantage it would give us? Why just the time saved alone would be astounding. Have you ever tried to put a pair of glasses or contact lenses on a tadpole or full grown frog? Its not easy.
air and light and time and space
what would stop
them from changing the spectrum of vision? perhaps adding uv or infrared to the normal visible light
Firstly, such an eye would have very few advantages on a microcamera - in terms of ease of use, it would be much simpler to hide tiny cameras in artificial cavities in someone's body than to do what you're proposing. Furthermore, the nervous system requirements to process the additional information simply are not there (infrared = red and your superspy can't see normal colors? Ooh, sign me up today.)
In order to do what you're proposing, you'd need to take a human eye and genetically modify it so that it could safely detect either infra-red or UV light, problems with that proposal include -
1) The human eye works by converting photons in the visible range into electrical potentials, which then produce nerve impulses. Photons are converted into electrical potentials by chromphores (big, organic molecules with many double bonds.) These chromophores can allready detect UV, but when they do they're destroyed. There's a membrane in the eye that exists purely to screen UV out. So, if you want to be able to see UV, you have to modify all the receptors that are allready in there to resist UV.
2) Genetic modification of these chromophores is exceedingly difficult, since they are not coded for by genes in and of themselves (they are produced by a host of other proteins.) So, you'd need to replace the dozen or so proteins that make a chromophore (in a particular cell, at a particular time) with a dozen or so genes/proteins that make some UV (or IR) sensitive chromophore. Then, you'd need (somehow) to alter all of the proteins that recognised the old chromophore so that they recognise the new chromophore, instead, so that it is properly inserted into the cellular architecture. This sort of technology is, optimistically, a century away, and has many more sinister potential uses than making an organic wide-spectrum camera.
3) It is extremely difficult, using only organic molecules, to distinguish between IR and physical heat. Unlike infrared light, which makes bonds bounce back and forth more quickly (= heat), or ultraviolet light, which cleaves bonds (in addition), visible light has the property of raising the electric potential of "pi" electrons; electrons which participate in a double bond but which are not strictly required for the bond to exist. Note that by this definition "visible" light does extend a little farther in each direction than what we can actually see.
After you've finished your epic feat of genetic and chemical engineering, you need to take your modified cells and insert them into embryos who have had there eyes removed and see if the modified cells still grow into eyeballs. I envy your budget.
The good and new comes from no quarter where it is looked for, and is always something different from what is expected.
The issue with the kittens is that the parts of their brain that would be used for that eye get taken up by other functions. Research seems to show that, if you had eyesight during that critical learning phase, and then lost it later, the brain function is still there and you should be able to recover your sight.
As well, even if it were only useful in immature organisms, it could be marvelous for kids who are born blind at birth (obviously in cases where there is simple physical eye damage). Further, my brother has Retinitis Pigmentosa, which is a progressive eye disease where he loses his peripheral vision. He still has fine eyesight in the little field he has; he can read, but is very likely to trip over large objects because he can't see them in his peripheral vision. As he likes to say, "I'll see the penny on the other side of the room; I'll just trip over an elephant I didn't see on the way there." As I understand it, his problem is entirely in his eyeballs; if you could replace them, it would completely solve his problem (until RP showed up in them again 30 years from now, assuming that the cause isn't local to the eyeball).
I do have concerns as well that the eye would be able to hook up. But I think a good analogy might be the cochlear implants for deaf people. They hook up in adults, but the inputs are so different from the natural ones that most adults never learn to integrate the information. However, with a grown eyeball, that shouldn't be a problem - the information should be very similar to what they used to receive.
Still exciting stuff, if only from a biohacking standpoint...