Thursday, November 06, 2008

First post

Here is today's nifty piece of medical progress, an advance in the fight against cancer. A couple years ago, an unfortunate woman died of acute myelogenous leukemia, leaving behind samples of her cells, some healthy and some cancerous. A team at Washington University in St. Louis was able to sequence the DNA from the cells and compare her healthy DNA to her cancerous DNA. This became possible because the price of DNA sequencing equipment has come down by a very large factor in recent years.

They identified ten point mutations that differentiated the sick cells from the healthy ones. Two of the mutations were already known from earlier research, the other eight mutations were previously unknown. The team is continuing to study differences in the non-coding DNA as well, and they are also preparing to apply the same sequencing methodology to other cancers.

Because they were using DNA samples all from the same person, there would be very few differences among the healthy cells, just the infrequent cell-to-cell mutations that might occur in an average healthy person's body. So they had a good solid statistical baseline that made the ten cancer-related mutations really clear.

It may be years before this translates into clinical practice that saves lives. But it's nevertheless an important advance. It's something that has never been done before, and it does bring to light a few new facts. It looks strongly like point mutations are the cause of at least some, possibly all, cancers. We strongly suspected that before but this almost proves it. One of the ten mutations was present in only a fraction of the cancerous cells, suggesting that the mutations typically occur in a particular sequence, with the last one finally making the cell dangerous.

I'm interested in what social and economic factors could most hasten the rate of medical progress. My reason for this interest is simple: I'm not young any more. I'm curious about whether the development model that has been so successful for open-source software could somehow be applied to quicken the pace of medical progress.

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