Single large-scale mitochondrial DNA deletion in a patient with mitochondrial myopathy associated with multiple symmetric lipomatosis.

In a nonalcoholic woman with multiple symmetric lipomatosis (MSL), muscle histochemistry showed ragged-red fibers and cytochrome c oxidase negative fibers. Southern blot analysis revealed a single deletion of mitochondrial DNA (mtDNA). We suggest that MSL is an uncommon manifestation of the wide clinical spectrum of mitochondrial disorders, in particular of those associated with single mtDNA deletions.