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Heart disease gene uncovered – Audio

Marion Greaser, Professor
Department of Animal Science
UW-Madison College of Agricultural and LIfe Sciences
Phone (608) 262-1456, (608) 262-1066

3:14 – Total Time

0:20 – Strange samples discovered
0:52 – What was found
1:11 – On the trail of a heart disease
1:31 – 1 in 500 people affected
2:07 – Rare rat genetic disorder
2:27 – Long research process
2:39 – Where the research will go
3:05 – Lead out


A heart disease gene uncovered, we’re visiting today with Marion Greaser, Department of Animal Science, University of Wisconsin in the College of Agricultural and Life Sciences, Madison, WI and I’m Sevie Kenyon.

Sevie Kenyon: Marion, you’ve been looking at proteins, can you give us an idea of what you found?

Marion Greaser: We’re working with cardiac muscle tissue and we’re trying to understand how this tissue works. We’ve been studying a giant protein called titin for a long time and during this sort of study why we just happened to be looking at changes in titin during development using the rat as a model animal. Surprisingly, we found some samples that didn’t seem to behave the way all the rest of the samples did.

Sevie Kenyon: What did you find at that point?

Marion Greaser: Well, it seems that these unusual samples were all from the same litter of rats and so it looks like then we’ve got some sort of a genetic mutation that’s affecting the size of the titin.

Sevie Kenyon: And where does this titin size protein fit into the situation?

Marion Greaser: There’s a relationship between the size of the titin and human health. People that have some cardiomyopathys have altered size titins and so that made this sort of finding quite interesting.

Sevie Kenyon: How common is the cardiomyopathy?

Marion Greaser: It occurs in one in maybe 500 individuals so it’s a quite common human disease. The particular form of cardiomyopathy that we’ve discovered related to the titin is probably a bit less than that. Still it’s a significant number of people that have this sort of problem. Everyone who is in the titin field is just amazed that we found this thing and we were amazed as well.

Sevie Kenyon: Marion, tell us a little bit about these rats.

Marion Greaser: Well if you just looked at them you wouldn’t notice there was much difference. They seem to be reasonably healthy. Although, they finally developed what’s known as dilated cardiomyopathy, which means the heart gets larger, thinner walled and doesn’t pump as well.

Sevie Kenyon: How long has this process taken you?

Marion Greaser: Well we made the original observation on these strange samples almost ten years ago. It’s a slow process.

Sevie Kenyon: And Marion, where does this research go from this point?

Marion Greaser: From here, one can take a look and see whether there might be some compounds that might affect the expression of this RBM20, this splicing factor that we’ve discovered that we could maybe alter the expression. Or looking long-term why we may be able to reinsert this gene into people and be able to restore normal function.

Sevie Kenyon: We’ve been visiting with Marion Greaser, Department of Animal Science, University of Wisconsin in the College of Agricultural and Life Sciences, Madison, WI and I’m Sevie Kenyon