REHOVOT, Israel - Scientists in Israel have created a model of a human embryo from stem cells in the laboratory, without using sperm, eggs or a womb, offering a unique glimpse into the early stages of embryonic development.
The model resembles an embryo at day 14, when it acquires internal structures but before it lays down the foundations for body organs, according to the team at Israel's Weizmann Institute of Science.
The scientists' work was published in the journal Nature on Wednesday after a pre-print came out in June, during the International Society for Stem Cell Research (ISSCR)'s annual meeting in Boston.
The Israeli team emphasised that they were a long way from being able to create an embryo from scratch.
"The question is, when does an embryo model become considered an embryo? When that happens, we know the regulations. At the moment we are really, really far off from that point," said team leader Jacob Hanna.
However, they said the work could open the door to new ways to test the effect of drugs on pregnancies, better understand miscarriages and genetic diseases, and perhaps even to grow transplant tissues and organs.
"They are not identical. There are differences from human embryos, but still, this is the first time, if you open an atlas or a textbook, you can say - yeah I can really see the similarity between them," said Hanna.
However, they said the work could open the door to new ways to test the effect of drugs on pregnancies, better understand miscarriages and genetic diseases, and perhaps even to grow transplant tissues and organs.
"They are not identical. There are differences from human embryos, but still, this is the first time, if you open an atlas or a textbook, you can say - yeah I can really see the similarity between them," said Hanna.