It's just not fair!

Zebrafish geneticists get to have almost as much fun as the insect geneticists. Today's example is brought to you by the journal Proc. Nat. Acad. Sci. USA:

... mutant lines of zebrafish defective in genes necessary for a functional heart. For example deadbeat and heartstrings are documented to possess cardiac defects...

I mean, how cool is that? Okay, it's not quite as cool as Makes Caterpillars Floppy, but still...