MITOCHONDRIAL-DNA MUTATIONS IN HUMAN-DISEASES - A REVIEW

Human mitochondrial diseases have been associated recently with mitoch ondrial DNA mutations, duplications and deletions which impair the pro tein synthesis of the mitochondrial subunits of the respiratory chain complexes. A constant feature is the coincident presence of the mutate d and wild type genomes which provide heteroplasmy. The clinical expre ssion of these diseases depends on the relative expression of each kin d of mitochondrial DNA in the various tissues, which in turn affects t he production of ATP in these tissues. Research on nuclear gene produc ts interfering with mtDNA or with its gene products is the next step t owards understanding the etiology of these diseases.