It’s also not yet clear how directly the mechanism carries over to humans. “You could imagine there’s a similar mechanism, but there’s no demonstration yet,” says Vincent Galy, a biologist at the Pierre and Marie Curie University in Paris who was not involved in the work.
The CPS-6 protein is similar to one found in humans, and it controls cell death similarly in both species. But because research in flies and mice suggests that exactly when sperm lose their mitochondria varies from species to species, the process itself probably varies slightly.