Let's start with a study of mice by Randy Jirtle. I understand these are known as Agouti Mice. Is is this something from the High Andes the Agouti Mice what does Agouti mean, and why why is this study that you did now so often cited as being important for understanding epigenomics? - So Agouti just means Brown. -- oh -- it's not not too exciting so you have two mice, I call these the Agouti sisters so from the hot dutch study and the Chinese famine studies, you knew that something occurring very early in development, literally in the first trimester of development, ultimately gave rise to increased susceptibility to diseases, including cardiovascular disease, obesity, diabetes and a doubling or tripling of the incidence of schizophrenia. So severe lack of nutrition early in development results in all of these disease characteristics 20-30 years later. The real problem though was what, is the mechanism by which the glue, the gravity, the molecular mechanism that holds these two disparate time points together. And this is how this study, why this study is so important. So the only difference between the brown mouse and the yellow mouse on this slide is what the mother was exposed to when they were in utero. these are genetically identical mice. the mother on the left, the yellow mouse, that mother was just eating normal Mouse Chow. the mother on the left was eating mouse chow that was supplemented with things like folic acid, choline, etc. Why those compounds? Because they're the ones that provide the methyl groups that are placed down onto the DNA all those methyl groups that are needed for programming come in from our diet. So that's why this early time point is so important. So here you have a mouse that is small, lean and clean, doesn't get diabetes, doesn't become obese. the only reason is because what had happened, and what that offsprings mother ate very early in development, and what we showed is, in this system anyway, that that molecular mechanism that relates these two time points together is DNA methylation at a region that's upstream is Agouti Mouse. So for the first time we showed that small changes in nutrition can alter disease susceptibility, not through alterations in the genome, but by alterations in the epigenome and this is fundamental. -- And one can already imagine the potential for, I believe we're already in some courts, legal responsibilities of mothers -- It's possible I don't get into the legal aspects. I have enough travel with the scientific crowd. --Right, but the work you all have done is now made this a very sensible question. --Exactly and there's real potential for good from this, if we can understand how to protect. -- I like to think about and focus on the good aspects of this, rather than the negative aspects. -- Right and you have good reason though to believe that these may be mechanisms that may be not totally unlike our own. -- It looks like from some of the model genes that we've been looking, at for example these imprinted genes, that indeed is the case. You can see environmental alterations the epigenome of these regulatory elements