TM6SF2 and metabolic dysfunction-associated steatohepatitis: Moreover, the molecular pathogenesis of lean NASH, although it shares fundamental mechanisms with obese NASH, is characterized by significant genetic predispositions (e.g., PNPLA3, TM6SF2, MBOAT7), dysfunctional adipose tissue (even in lesser amounts), distinct gut microbiome signatures, and modified adaptive metabolic responses.