Scientists have created synthetic human embryos without using male sperm or female eggs.

The work was recently announced by researchers at the annual meeting of the International Society for Stem Cell Research. It was a joint effort by the California Institute of Technology and the University of Cambridge, led by Professor Magdalena Żernicka-Goetz.

Professor Żernicka-Goetz told The Guardian newspaper that the result of her work was "beautiful."

"Our human model is the first three-lineage human embryo model that specifies amnion and germ cells, precursor cells of egg and sperm. It's beautiful and created entirely from embryonic stem cells."

Żernicka-Goetz and her researchers, alongside other scientists at the Weizmann Institute in Israel, have previously shown that mice stem cells can be developed into embryonic structures with a primitive brain, intestine and working heart. Scientists have subsequently worked to replicate that in human embryo models.

Precise details of the latest work have not been published. However, Żernicka-Goetz has confirmed that her team developed synthetic human embryos to the equivalent of 14 days for a normal embryo.

The development milestone is called gastrulation. Gastrulation is when the embryo changes from a sheet of cells to particular cell lines, and the building blocks of the body are established. There is no brain, heart or intestine yet - but the synthetic model displayed primordial cells, which are precursor cells of sperm and egg.

The work was reportedly done to help scientists examine the early stages of the human life cycle and to better understand why some women suffer pregnancy loss.

There is no stated suggestion to further grow the synthetic embryos, days or weeks old, into older babies. The basic science has involved creating synthetic embryos, 'embryo models', from stem cells rather than a combination of sperm and eggs. But the cells used in the experiment came from a normal baby embryo in a laboratory.

Stem cells are capable of replicating anybody's cell and can be manipulated to become embryos.

Source