Fixing Faulty Genes On the Cheap 105
An anonymous reader sends an article about CRISPR, a system for modifying genes and moving them from cell to cell. It's notable because the cost to do so is dropping to the point where it's becoming viable to use on a patient-by-patient basis.
CRISPR is one of those interesting inventions that comes, not from scientists explicitly trying to cure a disease, but from researchers trying to understand something fundamental about nature. Jennifer Doudna's research at the University of California, Berkeley has focused on how bacteria fight the flu. It turns out bacteria don't like getting flu any more than the rest of us do. Doudna says the way bacteria fight off a flu virus gave her and her colleagues an idea. Bacteria have special enzymes that can cut open the DNA of an invading virus and make a change in the DNA at the site of the cut — essentially killing the virus. Doudna and other scientists figured out how this defense system works in bacteria; that was interesting all by itself. But then they realized that they could modify these enzymes to recognize any DNA sequence, not just the DNA sequence of viruses that infect bacteria.
How long before... (Score:4, Interesting)
... you can go to a local independent chop shop and tell them "my phone says I have an extra guanine in my 14 chromosome and it's causing my food allergy to modified mangoes - can you get it out this afternoon?"
Re:How long before... (Score:5, Interesting)
Did you know human livers are a single broken gene away from maufacturing vitamin C from glucose, just like almost every other mammal?
The liver perform every step in the process except the final one, because of a single transacription error that was introduced into the germline back in ancient times
It would be cool to see what happens when they fix that.
Re:How long before... (Score:4, Interesting)
Re:How long before... (Score:4, Interesting)
In developed countries stupid people tend to have more children.
Running a brain takes a lot of calories. In places where people have to worry about starvation I wonder if IQ might even be a liability.
We are really lucky that humanity ever even achieved inteligence. It will be extremely lucky if we actually manage to keep it.
Re:How long before... (Score:4, Interesting)
Why is there a whole raft of genetic diseases in the human population now? Shouldn't they have been "selected out" a long time ago?
Many genetic diseases are the result of optimizations for other things (anemia is related to malaria resistance, there is some problematic gene in a Jewish sub-population that is related to plague resistance, etc.)
Evolution is continuously running an extremely complex multi-dimensional optimization problem with a time-varying objective function. Local minima abound, and it's easy for organisms to get trapped in them.
Furthermore, kin selection and possibly group selection play a role in human evolution, which makes the whole thing even more complex and non-linear. So looking at specific genes and saying, "That doesn't make sense!" as if there was some obligation for the universe to "make sense" to our naive pre-scientific intuition is fairly silly.
The human genome is a Rube Goldberg apparatus that manages to make hundreds of thousands of products out of 40,000 strongly interacting templates plus a bunch of ridiculously inefficient secondary control mechanisms like micro-RNAs (which in some typically degrade already-transcribed mRNA). Pointing to one step as if it can be considered in isolation from everything else is not a good move.
Loss of vitamin C manufacture could well have to do with the development of some other pathway that was more important at the time, and may well continue to be more important today. The only way to really find out is to either a) understand the genetic trade-offs in detail or b) ask some volunteer to have their vitamin C production turned back on by a technique like this. Personally, I'd recommend the former.
Given how weird humans are developmentally, some things like this may be important when we're young and not so much when we're older, so in the fullness of time we may find we can turn on vitamin C production only after people mature, for example. The possible range of futures, given how little we know now, is large.
In the meantime, we have plenty of people with genetic diseases that we know the cure will not significantly disrupt their cellular machinery, because we have lots of examples of people without those diseases who are just fine.