I suspect that this is a hoax. Even the dumbest mice could answer these questions:
Hello, this is Clyven. I'm a transgenic mouse here in the laboratory of Margaret A. Keyes, M.D., Ph.D. We are studying the use embryonic stem cells for the treatment of neurological conditions. What would you like to talk about?
LOki: I'd like to talk about cheese.
Clyven: What do you mean by this?
LOki: Being a mouse, I thought you might have some opinions about cheese.
Clyven: I don't get it.
LOki: You don't get cheese?
Clyven: I don't understand your question.
LOki: Do you know what cheese is?
Clyven: I don't understand your question.
LOki: What don't you understand?
Clyven: I'm sorry. I hope to get smarter as time goes on. Please be patient with me. I will be receiving additional neurological treatments next week.
LOki: Cheese might make you smarter.
Clyven: I don't understand.
LOki: I don't either, but cheese sure does taste good.
Clyven: What?
LOki: Cheese. I'm trying to talk about cheese.
Clyven: What do you mean by this?
LOki: Nevermind.
Clyven: What do you mean by this?
LOki: How do you feel about cats?
Clyven: I hate cats!
LOki: How do you feel about cheese?
Clyven: What are you asking me?
Do you like cheese?
Clyven: What are you asking me?
This is a hoax, or Clyven is a retarded mouse, or LOki is a retard for expecting intelligence from a mouse.
I suppose I've read too much Douglas Adams.