Полиморфизм клинических проявлений прогрессирующей митохондриальной энцефаломиопатии, ассоциированной с мутацией гена POLG1

The common cause of mitochondrial diseases is mutations in the POLG1 gene encoding the catalytic subunit of DNA-polymerase gamma that is responsible for the replication and repair of mitochondrial DNA. Diseases associated with POLG1 gene defects are characterized by obvious clinical polymorphism and may resemble some mitochondrial syndromes and other hereditary and nonhereditary diseases, which gives rise to diagnostic difficulties. Another characteristic feature is that phenotypic manifestations are of diversity in various patients having the same mutation in the POLG1 gene. The paper describes mitochondrial encephalomyopathy, caused by homozygous mutation in the polymerase gamma (POLG1, p.L304R), with different clinical manifestations and a poor outcome in patients from two different families.