- Scientists in Israel and the United States successfully created a new type of embryonic stem cell which only has one copy of the human genome, rather than the usual two. Published in Nature, the findings could help with genetic research for oncology and precision medicine.
- The new stem cells are the first human cells to be discovered which are capable of cell division with only one set of chromosomes.
- Typically, a human cells carry two sets of 23 chromosomes, except for reproductive cells which only carry one set. Reproductive cells, however, can't divide and make more copies of themselves.
The scientists, from The Hebrew University of Jerusalem, Columbia University Medical Center, and The New York Stem Cell Foundation Research Institute, hope their discovery can help make gene editing easier.
""One of the greatest advantages of using haploid human cells is that it is much easier to edit their genes," said Ido Sagi, the lead researcher at The Hebrew University. Since human cells carry two copies of genes, it is more difficult to see the effects of a mutation in one copy as the other functions as a backup.
In order to generate the new type of cells, the scientists triggered unfertilized human egg cells to divide and isolated the resulting single-copy stem cells from normal diploid cells using a fluorescent dye. These single-copy stem cells were able to "differentiate" into a number of other human cell types, even as they retained the single set of 23 chromosomes.
Another member of the research team, Nissim Benvenisty said “these cells will provide researchers with a novel tool for improving our understanding of human development, and the reasons why we reproduce sexually, instead of from a single parent.”