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Leber遗传性视神经病变(LHON)是一种常见的与线粒体突变相关的母系遗传性疾病,在不同种族人群的LHON家系中,有50％以上是由于线粒体DNA(mtDNA)编码呼吸链复合体Ⅰ上ND1 G3460A、ND4 G11778A和/或ND6 T14484C的原发性突变引起的.然而,线粒体病呈现多样化的表型,相同的线粒体DNA突变可以产生不同的表现型,且不同的mtDNA突变又可以产生相似的表现型.LHON临床表型的多样性、男性多发、不完全外显和不同的基因表现度等现象提示还有其他因素(如环境、核修饰基因等)对疾病的发生及发展过程起到修饰作用,而环境因素如慢性氰化物中毒、吸烟、饮酒、创伤应激、营养缺乏及mtDNA甲基化等均可能影响正常的线粒体功能.因此,环境与基因遗传模式的相互作用可能对LHON产生影响.“,”Leber hereditary optic neuropathy (LHON) is a maternally inherited disorder associated with mitochondrial DNA (mtDNA) mutations.In the LHON families in different ethnic backgrounds,the mutations of ND1 G3460A,ND4 G11778A and/or ND6 T14484C in the genes encoding subunits of respiratory chain complex Ⅰ account for more than 50％.But,as we know,the phenotypes of mitochondrial diseases are varied,so the same mutational points may generate different clinical phenotypes,and conversely,different mtDNA mutation variants may generate the similar phenotypes.Some states of LHON including the prone to male,incomplete penetrance,and phenotypic variability of vision loss suggest that other modifier factors probably play a synergic role in the development of LHON.Environmental factor,such as chronic cyanide poisoning,smoking,drinking,trauma,nutrition deficiency and mtDNA methylation,affects mitochondrial function.Therefore,there is an inheritance of gene and environment interactions affecting LHON.