Mutations in the TAZ gene, encoding the cardiolipin remodeling enzyme tafazzin, are causal for the inherited cardiomyopathy Barth syndrome.

Defective tafazzin function results in a plethora of mitochondrial defects including mitochondrial morphology, electron transport chain formation and function, and an increase in reactive oxygen species production.

A mitochondrial quality control AAA protease contributes to the Barth syndrome phenotype by degrading mutant tafazzin proteins, and works together with tafazzin to ensure that misformed and reactive oxygen species producing mitochondria are effectively degraded by mitophagy.