TGFB1 and inborn mitochondrial metabolism disorder: GDF15, a distant member of the TGF-β superfamily, has emerged as a strong biomarker in multiple other pathological or physiological states, such as mitochondrial disease (14), liver fibrosis (15), myocardial infarction (16), aging (17), and nonalcoholic steatohepatitis (NASH) in a recent SomaScan study (7), but to our knowledge has not yet been linked clinically to AH.