MAT1A and metabolic dysfunction-associated steatohepatitis: Finally, analysis of serum metabolomes of patients with NAFLD allowed to identify three distinct subtypes of NAFLD, based on their similarity to the metabolome profile of methionine adenosyltransferase 1a knockout (MAT1A-KO) mice, which have chronically low level of hepatic s-adenosylmethionine, and spontaneously developed NASH [33].