Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) are 2 monogenic cerebral small vessel diseases sharing several common clinical features including young stroke, migraine, and cognitive dysfunction. The aim of this study was to understand the role of MELAS in patients with CADASIL-like manifestations. We screened 429 unrelated patients with genetically unassigned CADASIL-like syndrome for mitochondrial DNA m.3243A>G mutation. None of them were found to have the mutation. Our finding suggests that m.3243A>G rarely causes CADASIL-like phenotype. It may be not necessary to consider MELAS as a differential diagnosis of CADASIL. Screening m.3243A>G in patients with CADASIL-like phenotype is of limited value.

中文翻译：

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线粒体 DNA m.3243A>G 突变很少引起 CADASIL 样表型

线粒体脑肌病、乳酸酸中毒和中风样发作 (MELAS) 和伴有皮质下梗死和白质脑病的常染色体显性遗传性脑动脉病 (CADASIL) 是 2 种单基因脑小血管疾病，它们具有多种常见的临床特征，包括年轻中风、偏头痛和认知功能障碍。本研究的目的是了解 MELAS 在具有 CADASIL 样表现的患者中的作用。我们针对线粒体 DNA m.3243A>G 突变筛查了 429 名基因未分配的 CADASIL 样综合征的无关患者。他们都没有被发现有突变。我们的发现表明 m.3243A>G 很少引起 CADASIL 样表型。可能没有必要将 MELAS 视为 CADASIL 的鉴别诊断。在具有 CADASIL 样表型的患者中筛查 m.3243A>G 的价值有限。