TAFAZZIN and Barth syndrome: To obtain a more suitable mouse model for developing new therapeutics for Barth syndrome, we here characterized mCK-Cre conditional Taz knockout mice, in which the cardiac and skeletal muscle selective mCK-Cre transgene (Brüning et al., 1998) catalyzes inactivation of the floxed Taz allele (Ren et al., 2019; Wang et al., 2020).