Editor's note: The original 60-Second podcast version is here

Schizophrenia typically shows up in young adults. For men it tends to emerge around 20 to 28 years and peak onset for women is between 26 to 32 years. But what triggers the disease during this time? Well past studies have shown that mutations in a gene called DISC1 are linked to schizophrenia. DISC1 enables a guide to new nerve cells—sort of like a traffic cop—sending them to the right place to make the right connections to other cells. But recently, researchers partially shut off DISC1 in lab mice to see what happens when there is no traffic cop. And what they saw is a steady decrease in the size and number of dendritic spines, the tiny branches of the nerve cell that receive messages from nearby cells. Their results are published in the March issue of Nature Neuroscience. Connections between cells are continously broken and forged throughout our lives but there is an amazingly large amount of so-called “pruning” during adolescence. So if this breaking of connections goes awry, as it does when DISC1 is shut off, then one might be at high risk for schizophrenia. And so whereas the defective gene may be there at birth, its effect does not show up until many years into one’s life, post adolescence in young adulthood.