Mice are still the best model for mammal genetics and physiology. Small, docile and cheap these little fellas are one of the main reasons why science (specially medical science) keeps advancing so quickly.
Nowadays many labs can generate mice lacking certain genes of interest by simple manipulation of mouse embryonic stem cells. There is a huge array of "mutated" mice strains about.
I thought it would be funny if they got together and discussed their griefs.
(p53 is a very important gene, involved in the development of cancer)