So non-alcoholic steatohepatitis is a progression of fatty liver disease. Dr. Anton Titov, MD.: How does NASH actually differ from any NAFLD? So NASH confers or implies that in addition to fat, so remember, NAFLD is kind of an umbrella term. And most patients with NAFLD have plain fat. Sometimes we call that non-alcoholic fatty liver, but a subgroup will not only have fat, but they will have inflammation, injury to hepatocytes, and the beginning of the development of scarring. So it's the inflammation, injury, and scarring component that defines NASH. It is more than just simple liver fat alone. Dr. Anton Titov, MD.: What drives the progression from NAFLD to non-alcoholic steatohepatitis, NASH? We wish we knew. There are a lot of hints. So, for example, as I mentioned, most patients with fat in the liver have nothing but fat. And that's not a cause for alarm. It certainly tells us that the patient is at risk for more advanced liver disease. Dr. Scott Friedman, MD.: But again, most patients don't have fat. And yet that subset of patients who go on to develop NASH have an increased risk of complications. we don't know why some patients only have liver fat and others will progress to NASH. As I mentioned, diabetes is one of the risk factors. There may also be genetic risk factors. Now, they're not the most dominant cause of liver fat and progression to NASH. Dr. Scott Friedman, MD.: But we do know that there is a growing list of genes with single base pair or DNA sequence changes that collectively can increase or decrease the risk of progression from fatty liver disease to NASH. Certainly, family history, which is probably a surrogate for genetics, but also for a shared microbiome and diet. Family history can be very important. So if a patient tells me that their parents had or one of their parents or a sibling had NASH, that raises my index of suspicion considerably that they too may have NASH and not just simply plain fat in the liver.