Facile detection of mitochondrial DNA mutations in tumors and bodily fluids

Examination of human bladder, head and neck, and lung primary tumors reveal ed a high frequency of mitochondrial DNA (mtDNA) mutations. The majority of these somatic mutations were homoplasmic in nature, indicating that the mu tant mtDNA became dominant in tumor cells. The mutated mtDNA was readily de tectable in paired bodily fluids from each type of cancer and was 19 to 220 times as abundant as mutated nuclear p53 DNA. By virtue of their clonal na ture and high copy number, mitochondrial mutations may provide a powerful m olecular marker for noninvasive detection of cancer.