Coronal sections through the forebrains of six different example secretory-trap mouse lines at birth, showing the variety of axonal pathways labeled by the PLAP marker. The genes trapped in each case are indicated; LST16 and KST37 are examples of traps in new genes. Abbreviations: ac, anterior commissure; cc, corpus callosum; co, cortex; f, fimbria; fx, fornix; h, hippocampus; ha, habenula; pc, piriform cortex; st, striatum; str, stria terminalis. See Leighton et al. [6] for further details.