Researchers Identify Gene That Starts Human Embryo Development

Researchers have identified the gene that initiates the developmental program resulting in cells forming a human body. The gene, called NANOG, was studied by making precise changes to the DNA of fertilized eggs using CRISPR base editing. The work shows that NANOG has a different role in human embryos than in mice.

When the gene was disabled in human eggs, none of the cells developed into those that form the embryo. In mouse eggs, disabling the gene prevented cells from developing into yolk sac progenitors.

Base editing changes a single DNA letter at a time.

Researchers say the precision of the technique reduces the likelihood of unintended chromosomal abnormalities compared with the original form of CRISPR. The study used eggs donated by women undergoing IVF treatments. Embryos that lacked NANOG still appeared normal under a microscope, though they lacked the potential to form the embryo proper.

A better understanding of early human development could help improve IVF success rates. Researchers noted that embryo selection for implantation is currently based largely on shape, and identifying key genes like NANOG might provide additional markers. The same knowledge could advance stem cell research and regenerative medicine. The study was published in the journal Nature.