Learning About Early Development Studying Non-human Embryos
This is just a 10 minute talk for the UC Irvine OLLI (Osher Lifelong Learning Institute) covering the Science Breakthroughs of the Year, 2021 by Science Magazine.
Optogenetics or “xyztg” tracing the development of embryos.
Recently, the development of embryos by cells in space and time, as well as in genetic content, has been achieved. This is called Optogenetics or “xyztg” tracing. The scientific breakthrough in 2021 was the discovery that by rotating the jar containing the nutrient broth and adjusting the oxygen levels, they can study mouse embryos development from not only 3 to 4 days, but to 11 days. In that time the cells grew organs and developed hind legs. In mapping the genes, they use genetic inserts that can light up.
Here is a photo from 2018 of the cells growing.
Studying initial cell growth is important for understanding human miscarriages and birth defects, as well as in-vitro fertilization protocols. Since they cannot study human blastocysts directly, they also can now make them from reprogrammed adult stem cells, that will not make human babies. In humans, the embryo becomes a blastocyst of about a hundred cells in the 5th to 6th day from fertilization, where it becomes implanted in the uterus. In in-vitro fertilization they choose developed blastocysts as having the highest chance of implantation.
One study from UC Berkeley showed that half of fertilized eggs do not make it to natural births. Even for women who know that they are pregnant, miscarriages will occur for 10%-20%, half from chromosomal defects and half from other factors.
