University of Vermont

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Transcript: Variations on a Gene

Katie St. Denis, senior zoology major

Katie is researching malaria parasite genetics in the lab of UVM faculty member Joseph Schall

Dr. Schall: If you are a music major, you'll eventually touch an instrument. I mean, it would be absurd to be a music major and not handle instruments. And if you're a science major, you have to discover things. You have to get into the lab. Research is a creative activity of science, so for a student to go through four years as an undergraduate and never get into a lab and make a discovery, that's like never touching the instrument.

I met Kate St. Denis for the first time in my advanced course in parasitology. Katie sat up front and she had a habit of asking the most impertinent, difficult questions and every class the students would be giggling every time because they could see her hand go up and then they knew something was coming. And I thought "Well, that's the kind of person I want to have in my lab." so right away I suggested that she come and work with me. I figured that was to solve the problem of the student who asks impertinent questions is have her find answers for herself.

Katie: We have very little data right now, except for once species of human malaria parasite that has gone back so far with samples to constitute evolutionary time arguably. This would be the first such study to do that with a non-human malaria parasite so it's just good comparative data.

Dr. Schall: We have information on genes that are responsible for drug resistance. And we know that once we introduce a new drug for treating people with malaria, we know that very quickly the parasite changes. That can happen over just a few years. What about a parasite that's never been attacked by drugs? So we work with this parasite of lizards in California. So people aren't out there distributing pills to lizards. There is no interference in the natural system.

Katie: A parasite and it's host tend to coevolve in a kind of escalating battle of arms. One will try to fight the other and it constantly goes back and forth because it's not only evolving for each generation time, it's evolving to the host's immune system, which can happen in an individual over many generations of the parasite. So we expect that micro-satellite genes, which typically evolve faster than other coding genes, would tend to show a fair amount of variation of a period of years.

Dr. Schall: We have stored blood samples in the freezer going back all the way to 1995/96 and so Katie and I sat down and thought "Well, would it be worthwhile for us to see if we can detect an evolutionary change in the parasite over the past 14 years or so?" And then we have other blood samples stored in the form of microscope blood smears that have been stained. When you stain a blood smear, it's as though you are going out of your way to destroy the DNA and so to recover it is going to take some pretty fancy tricks. Katie was up for that and it would be a rare student for me to say "Go for it." because that involves a lot of very close attention but also the ability to keep focused and to do the same thing over and over again, try stuff, if it fails try the next idea; and Katie has that style. I found that out during her summer project.

So now she has genetic information for five spots in the genome from 2009 samples going back to the 95/96 range and now she is getting ready to start scratching microscope slides to see if she can get the dna off of those slides. She'll have a one-of-a-kind project, its going to take a lot more work to get it finished, and by the time she's done her senior project she's going to have another paper that everybody working with malaria and other microbes as well will want to read.

Katie: I definitely want to go to graduate school, I want a career in science, and I take that seriously. I really wanted to get started on it and get experience with it before I got to graduate school, before I made a career out of it, it's kind of a continual process. It doesn't just start at some set point when you are done with school, it's something that starts when you're in school.

Last modified April 23 2010 02:05 PM