Utah biotech claims it created working human sperm in the lab

Paterna Biosciences says it has grown functional human sperm from stem cells taken from testicular tissue and used them to create embryos. The company isolated and matured the cells in a lab dish. Co-founder Alexander Pastuszak says the lab-grown sperm look and function like natural sperm. Worth flagging: the work hasn't undergone peer review yet, so questions about whether others can replicate it and whether it's safe remain open.