Researchers Show How Stem Cells can be Turned into Egg and Sperm

In a first, a team of researchers from UK and Israel have used human stem cells to create precursors to sperm and egg.

According to TIME, researchers created primordial germ cells (PGC) from human embryonic cells. While PGC have earlier been created from rat embryonic cells, they have never been created with success from human cells.

"The creation of primordial germ cells is one of the earliest events during early mammalian development. 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. It has highlighted important differences between embryo development in humans and rodents that may mean findings in mice and rats may not be directly extrapolated to humans," said Dr Naoko Irie, first author of the paper in a news release.

A key finding in the study was the involvement of the gene SOX 17, which according to The Times of India was critical in the transformation of stem cells to PGC. Contrastingly, rat studies in the past have shown that this gene does not have much of a role to play in the rodents, indicating that results from rat studies cannot always be extrapolated for humans.

Researchers have also shown that adult cells like skin cells can be used to produce PGC, a development that raises hope for infertility treatment. The researchers also found that a process during PGC specification involves removal of most additions made to parent DNA by environmental factors like smoking, thereby ensuring replication of pure genetic information.

"The comprehensive erasure of epigenetic information ensures that most, if not all, epigenetic mutations are erased, which promotes 'rejuvenation' of the lineage and allows it to give rise to endless generations," said professor Surani.