Independent Corroboration...
Now, there are a lot of ways we can get at the issue of whether we're really seeing that much repair. The way excision repair is mesured in the lab is the cells are uniformly radiated. Then they're put in the dark. You get the idea. That point, when you kill them, it's a mercy killing, hardly a kind of natural situation. So we are having to adapt some of these techniques. One thing is I am looking at photoproducts. Are we seeing photoproducts build up in the time today that would fit into some of our hypothesis. There has been work done partly by Anita Buma, her and partly by Wayne Jeffreys of Florida, looking at DNA damage through the day in phytoplankton. The timing for where they're showing DNA damage occurs is exactly what you would expect and it fits in very well with our hypothesis.
I was very fortunate to get to spend a week with Anita in the Netherlands, actually two weeks ago. We tried to look for photoproducts in some of our samples and didn't find any. Just to give you an idea of how this is done, first of all we isolated the DNA. I did that at Ames. And then I brought that over to the Netherlands and we measured how much DNA we had for each little sample. Again, we got samples from every hour to two hours, 24 hours a day and three different treatments and replicates. We've got lots and lots of DNA samples. As my former post doc Charlie once said to me, I can't be upset about isolating 500 DNA samples because it's like contemplating the universe; it's beyond human comprehension.
|
Narrative Index
BioForum Index
