Question: What’s your theory on how embryos get enough energy to develop?

Paul McKeegan answered on 8 Nov 2017:

Well, it’s not just my theory, but my work supports the idea that the store of fat in the egg is more important than previously thought. Preimplantation embryos have to survive for about a week on their own until they can attach to the womb and start getting a supply of oxygen and nutrients from mum. Lots of lab work to date has shown that the embryos consume simple nutrients, like glucose and pyruvate, and amino acids during this time and if you want to grow embryos in the lab, the fluid needs to contain all of these in the right amounts. However my work and that of colleagues around the world has shown that releasing energy from the fat that is stored in the egg is really key to embryo growth during these first few days. If you prevent access to this fat using inhibitors, or force it to be used quickly, or change the composition of it through the culture fluid, or through an animal’s diet, you can cause lots of negative effects on the embryo’s development and use of its genetic code. But they definitely need the energy from this fat store to develop successfully!