Animal models are often needed in medical research because human samples cannot be reasonably obtained. Lynn Ferguson and Jim Kaput explain what makes mice an appropriate choice.
Morrinsville CollegeWhy is some of theresearch done on mice?
Lynn Ferguson (Because you can’t go straight through to people; you’ve got to be sure ... it's all very well at a cellular level to understand if something is going to be good, but you’ve got to understand if it’s going to be metabolised [processed by the body], if it’s going to be absorbed ... a whole pile of questions going from cells through to humans.
Facilitator: Why mice, not pigs?
Jim Kaput (The NCMHD Centre of Excellence for Nutritional GenomicsSo it turns out that about 100 years ago some people in the United States would breed mice just because they wanted different coat colours, like white, and brown, and black, and a couple in between. But what they found when they were breeding these to make coat colours, they also found out that they had some kinds of metabolic diseases. So that some of them that were dark black would develop if you fed it the wrong diet. So the geneticists realised that what was happening is they were selecting the genes in one of mouse, and they could use that by comparing it to another mouse, so that is one of the reasons why we did mice. We have a hundred years of for that.
Lynn Ferguson (And pigs ... to get enough of the food material to feed pigs, for example, when it’s an exploratory thing - you couldn’t do it.
Jim Kaput (The NCMHD Centre of Excellence for Nutritional Genomics The other reason that is related to the question of why mice? - mice have 99% of the same genes that humans do. In fact, almost every shares genes and pathways. So even though we don’t have tails, a lot of the that goes on in mice is identical to the metabolism that we have. And the things that differ, we now have computer programmes to understand them so we can to model it.
A lot of organisms have the same set of genes, which is true, we sort of like rearrange them all, and we turn them on and off at different times. We actually have some genes that could probably make a tail, but they’re not used any more. And so it’s a matter that when you become a, there is a certain pathway, a developmental pathway, that your genes take. And therefore you won’t ever get a tail; we can’t do that.