The first time in history, researchers have successfully used human embryonic stem cells to create primordial germ cells, cells that divide and mature into egg and sperm. Previously, the feat had been accomplished using rodent stem cells -- not those from a human embryo.

"Researchers have been attempting to create human primordial germ cells (PGCs) in the petri dish for years," leader author Jacob Hanna, a researcher in the Institute's Molecular Genetics Department, said in a released statement.

Stem cells are undifferentiated biological cells capable of dividing and transforming into specialized cells. They are the most basic of biological building blocks.

"The creation of primordial germ cells is one of the earliest events during early mammalian development," study co-author Naoko Irie, researcher at the Wellcome Trust/Cancer Research UK Gurdon Institute at the University of Cambridge, said in a press release.

"It's a stage we've managed to recreate using stem cells from mice and rats, but until now few researches have done this systematically using human stem cells," Irie added.

Researchers say the newly realized feat has revealed differences between embryo development in humans and rodents -- discrepancies that could undermine studies that extrapolate mice and rat-based evidence to human-related conclusions.

"Having the ability to create human PGCs in the petri dish will enable us to investigate the process of differentiation on the molecular level," Hanna said.

The research was published this week in the journal Cell.