An excellent example of the power of the yeast model is the use of yeast cardiolipin (CL) synthesis mutants to understand the metabolic abnormalities in Barth syndrome (BTHS), a rare genetic disorder caused by mutations in the CL-remodeling enzyme tafazzin (Bione et al., 1996; Vreken et al., 2000). The gene discussed is TAFAZZIN; the disease is hereditary disease.