Gene therapy for color blindness

How’s this for weird? This past semester I did a paper on color blindness, citing the different types, where the mutations occur, and the newest research. I was just about to post about one specific breakthrough when I got distracted by a list of the top scientific breakthroughs of 2009. As it turns out, number one has to do with gene therapy.

Two boys with X-linked adrenoleukodystrophy, a disease that ravages the brain, are doing well after French doctors gave them a gene that helps to maintain the delicate myelin coating on their nerve cells. A woman with Pachyonychia Congenita, a painful skin condition, watched one of her sores fade after doctors switched off the offending protein with a newer kind of gene therapy called RNA interference. Twelve patients who were blinded by Leber’s congenital amaurosis showed signs of recovery after getting a genetic treatment in one of their eyes. Italian researchers announced that most of the 10 patients who received gene therapy for severe combined immunodeficiency, or “bubble boy disease,” are doing very well eight years after the procedure that repaired their defenses against infection.

I especially love the implementation of RNAi. I strongly suspect its use will only increase in the coming years, especially in the fight against cancer.

Also this year, researchers at the University of Washington cured two adult monkeys of colorblindness by giving them injections of a gene that produces pigments necessary for color vision. After the treatment, the animals scored higher on a computerized color blindness test.

This one hits especially close to home. I also ‘suffer’ from color blindness, so I find it incredibly uplifting that I may not feel like I’m missing out on the things everyone else is seeing for the rest of my life. It isn’t that I can’t see color – I can – but colors become far less vibrant to me in lesser lighting. This happens to all humans, but it happens to those with color blindness sooner. I also cannot make fine distinctions, like the ones you see (literally) in the Cambridge Colour Test for color blindness. Take this for instance.

Most people will see a “6” there. I can make out some discoloration and the vague shape of a 6, but I wouldn’t be able to guess it without already knowing what to expect. I am likely deuteranomalous. It’s a pretty common type of color deficiency and it doesn’t especially affect daily life – I didn’t know I had it until 3 or 4 years ago during a routine eye exam (which I no longer need thanks to LASIK).

(And blah blah blah your monitor may suck or you may suck at coming up with a balanced coloring, so that test may not show up correctly in the first place.)

Genes and intelligence

More Evidence That Intelligence Is Largely Inherited: Researchers Find That Genes Determine Brain’s Processing Speed

In a study published recently in the Journal of Neuroscience, UCLA neurology professor Paul Thompson and colleagues used a new type of brain-imaging scanner to show that intelligence is strongly influenced by the quality of the brain’s axons, or wiring that sends signals throughout the brain. The faster the signaling, the faster the brain processes information. And since the integrity of the brain’s wiring is influenced by genes, the genes we inherit play a far greater role in intelligence than was previously thought.

What the study found was that myelin thickness corresponds to intelligence. That is, the more fatty covering of the axons in your brain, the more intelligent you are likely to be. And because myelin thickness is genetically linked, intelligence has a genetic link.

What’s important to remember here is that intelligence isn’t soley about genetics. We are not our genes. Environmental influences are still overwhelmingly strong in determining intelligence. Take the South. I doubt there’s really such a large contingent of people with thin myelin gathered below the Mason-Dixon line. It’s more likely a lack of education funding and general principles praising intellectual achievement (see last 50 thousand election cycles, especially the last three national elections).

Because the myelination of brain circuits follows an inverted U-shaped trajectory, peaking in middle age and then slowly beginning to decline, Thompson believes identifying the genes that promote high-integrity myelin is critical to forestalling brain diseases like multiple sclerosis and autism, which have been linked to the breakdown of myelin.

Weird how science does good things.