Not to be outshone by their Korean counterparts in genetic engineering—who this week caused a sensation with their “glow-in-the-dark” cats—Japanese scientists have created fearless mice.

“Cat and mouse may never be the same. Japanese scientists say they’ve used genetic engineering to create mice that show no fear of felines, a development that may shed new light on mammal behavior and the nature of fear itself.

Scientists at Tokyo University say they were able to successfully switch off a mouse’s instinct to cower at the smell or presence of cats — showing that fear is genetically hardwired and not learned through experience, as commonly believed.”