“We get stressed out and flooded with cortisol,” Kaminsky explains. “We have to wake up, fight or flight, run away, or just catch a cab to work. Cortisol is going to go up, but it should go back down again. We think SKA2 is important in that. If you have less, which is what we’re finding, then you’re going to have less of an ability to turn that off.”

The researchers first noticed the SKA2 mutation during a larger genome scan of postmortem brain samples from both healthy people and those with mental illness. Brains from people who had died by suicide had less of the SKA2 gene. Further, the researchers found evidence of an epigenetic modification, or a chemical change not in the DNA itself but the way it functions in the body.