Boule

'Human sperm gene 600 million years old' - Hindustan Times

The research has also revealed that Boule is the only gene known to be exclusively required for sperm production --from an insect to a mammal.

"This is the first clear evidence that suggests our ability to produce sperm is very ancient, probably originating at the dawn of animal evolution 600 million years ago. This finding suggests that all animal sperm production likely comes from a common prototype," lead scientist Prof Eugene Xu said.