Читать книгу Neurology - Charles H. Clarke - Страница 67

More than 70 different polypeptides interact to form the mitochondrial respiratory chain. Thirteen essential subunits are encoded by the 16.5 kb mitochondrial genomic DNA (mtDNA).

Mitochondrial diseases caused either by mutations in mtDNA or in mitochondrial genes are transmitted via maternal inheritance.

Examples are disorders such as myoclonic epilepsy and ragged red fibres (MERRF), mitochondrial myopathy, encephalopathy, lactic acidosis and stroke (MELAS) and Leber’s hereditary optic neuropathy (LHON). Chronic progressive external ophthalmoplegia (CPEO) is usually the result of a large deletion. A single mitochondrial disorder can present with variable features. For instance, the m.3243A>G point mutation may cause either MELAS, CPEO, diabetes mellitus or deafness.