Mitochondrial translation is essential for the biogenesis of the mitochondrial oxidative phosphorylation system (OXPHOS) that synthesizes the bulk of ATP for the cell. Mutations in either mitochondrial DNA or in nuclear genes that encode mitochondrial translation factors can result in impaired OXPHOS biogenesis and mitochondrial diseases with variable clinical presentations. Mutations in the FARS2 gene encoding the mitochondrial phenylalanyl-tRNA synthetase are commonly linked to either early-onset epileptic mitochondrial encephalopathy or spastic paraplegia. Here, we expand the genetic spectrum of FARS2-linked disease with three patients carrying novel compound heterozygous variants in the FARS2 gene and presenting with spastic tetraparesis, axial hypotonia and myoclonic epilepsy in two cases.

中文翻译：

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非致命性早发性脑病伴或不伴癫痫患者的新型FARS2突变

线粒体翻译对于线粒体氧化磷酸化系统（OXPHOS）的生物合成至关重要，该系统可合成细胞的大部分ATP。线粒体DNA或编码线粒体翻译因子的核基因中的突变均可导致OXPHOS生物发生受损和线粒体疾病，临床表现也有所变化。编码线粒体苯丙氨酰-tRNA合成酶的FARS2基因突变通常与早期发作的癫痫性线粒体脑病或痉挛性截瘫有关。在这里，我们扩大了三名患者携带FARS2基因中的新型复合杂合变异体并出现痉挛性四肢轻瘫，轴向性肌张力低下和肌阵挛性癫痫的三名患者的FARS2连锁疾病的遗传谱。