Understanding Embryo Growth

Embryo's were a hot topic in science in recent years, and are a hot topic in our current political climate. Because of the moral dubiousness and political volatility human embryo's are no longer used in scientific research. Therefore most of our knowledge on the development of embryos is accumulated by studying the embryological development of other species or by old (100 years or older) research. Scientists are paricularly fond of studying the embryos of mice and chicks. Mice are studied because they have several genes that are analagous to human genes so the knowledge on developing mouse embryo's can easily be applied to humans while chicks are used because the access to the developing embryo is relatively simple and does not require the sacrifice of the parent. Using these models we understand it that embryo's start as a perfectly spherical ball that --> it divides into the primitive streak and the endoderm --> the primitive streak becomes the mesoderm and ectoderm --> BLACK BOX --> primitive organs are created --> BLACK BOX --> these organs mature and develop into the baby. We also understood that an embryo's development is directed by gradients in the womb, and have some insight into what these gradients are. My team at my lab is now reversing the process and using stem cells to find gradients in the embryo by exposing stem cells to varying levels of certain signals and tracking their development. Right now, we have reached the first black box. Having created some neuroepithelial progenitors, we are thinking about how to access the first step of development in the black box -- he radial glia.