TAFAZZIN and Barth syndrome: Recent studies have shown that tetracycline-inducible gene knockdown suppresses Taz gene expression by > 90% and results in profound L4CL deficiency in cardiac and skeletal muscles of B6.Cg-Gt(ROSA)26Sortm1(H1/tetO-RNAi:Taz,CAG-tetR)Bsf/ZkhuJ, or TazKD mice, mimicking a biochemical phenotype of human BTHS [11–13].