BTHS is characterized by mutations in tafazzin, a phospholipid-lysophospholipid transacylase that is involved in the last step of the de novo biosynthesis of the mitochondrial-specific lipid cardiolipin (CL) (Barth et al., 1996; Bione et al., 1996; Vreken et al., 2000; Schlame et al., 2003). Here, TAFAZZIN is linked to Barth syndrome.