Schon E A, Hirano M, DiMauro S
Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY 10032.
J Bioenerg Biomembr. 1994 Jun;26(3):291-9. doi: 10.1007/BF00763100.
The classification of mitochondrial encephalomyopathies relied upon clinical, biochemical, and histological features until the discovery of mitochondrial DNA defects in 1988. Since then, an outburst of molecular genetic information has aided our understanding of the pathogenesis and the classification of these heterogeneous disorders. Novel concepts of maternal inheritance, mitochondrial DNA (mtDNA) heteroplasmy, tissue distribution, and threshold have explained many of the clinical characteristics. The discovery of point mutations, large-scale mtDNA deletions, duplications, and autosomally inherited disorders with multiple mtDNA deletions have revealed new genetic phenomena. Despite our rapidly expanding understanding of the molecular genetic defects, many questions remain to be explored to fill the gap in our knowledge of the relationship between genotype and clinical phenotype.
在1988年发现线粒体DNA缺陷之前，线粒体脑肌病的分类依赖于临床、生化和组织学特征。从那时起，大量的分子遗传学信息帮助我们理解了这些异质性疾病的发病机制和分类。母系遗传、线粒体DNA（mtDNA）异质性、组织分布和阈值等新概念解释了许多临床特征。点突变、大规模mtDNA缺失、重复以及伴有多个mtDNA缺失的常染色体显性遗传疾病的发现揭示了新的遗传现象。尽管我们对分子遗传学缺陷的理解迅速扩展，但仍有许多问题有待探索，以填补我们在基因型与临床表型关系知识方面的空白。
