Barth syndrome is an X-linked cardiac and skeletal mitochondrial myopathy. Barth 
syndrome may be due to lipid alterations because the product of the mutated gene 
is homologous to phospholipid acyltransferases. Here we document that a single 
mitochondrial phospholipid species, tetralinoleoyl-cardiolipin, was lacking in 
the skeletal muscle (n = 2), right ventricle (n = 2), left ventricle (n = 2), 
and platelets (n = 6) of 8 children with Barth syndrome. 
Tetralinoleoyl-cardiolipin is specifically enriched in normal skeletal muscle 
and the normal heart. These findings support the notion that Barth syndrome is 
caused by alterations of mitochondrial lipids.