Rights: The University of Waikato Published 1 May 2006 Download

Not only are there gene variants that make you more likely to be obese, an overload of food in your system can cause gene mis-expression, making it very easy to put on more weight. Jim Kaput from the University of California explains.


Paeroa CollegeWhat is the role of genes in obesity?

Jim Kaput (The NCMHD Centre of Excellence for Nutritional Genomics)

So what we are working on is that the concept that certain types of nutrients, particularly too much fat and too many calories, will change how your body expresses the genes so that they tend to make you heavier.

You have about 30,000 genes in your DNA, and maybe about 100 of them or so will be mis-expressed because of the amount of food you eat. And if you have that mis- expression, that means that you are making more of something or less of something, and that is a consequence of what you are eating. And then your body tries to respond to that, and in some cases it will put weight on.

Probably the biggest challenge that we have, is that when you see somebody who is overweight, or you see a Type II diabetes person, it looks like everybody is overweight the same way. But what we are finding is that there are different molecular pathways, there are different sets of genes that the variance in one person may be different in the variance in another person. And that’s why it is so challenging in normal types of science and medicine to try and look at somebody and know how to treat them, or know what to tell them what to eat. And what nutrigenomics is doing is trying to sort all those different pathways. And I think we’ve got a good chance of doing that. So in the future we will know why certain individuals are obese, and they might be 10 different ways to become obese genetically. And we are going to try and sort that out.

I have to work out everyday and I have to watch to what I eat otherwise I could be a little blimp. I don’t want to be a blimp.

Lynn Ferguson (Nutrigenomics New Zealand)

And there is someone in my lab who drives me crazy, because she eats chocolate, all the sorts of things that I wouldn’t dare eat, and she complains that she is too slim. So there are definitely genetic differences. I want to sort out that gene

Jim Kaput

We are going to get to the point where we will be able to say why you are obese, and then there might be specific diets that you can have to try to reduce it. And it’s also likely that some of the genetic problems could be done [managed] with pills. We try not to use the pills, or talk about them, but likely there are certain people that are not likely going to be able to control how much they gain, and then that is where we are going to need medicines in order to treat them.

Facilitator: Now will the origins of those medicines be in the foods that you isolate from nutrigenomics?

Jim Kaput

What we do is identify the food chemical, and then we modify it so it’s metabolised [or processed] more slowly. And because it’s metabolised more slowly, it acts s a drug rather than a food.