Department of Central Laboratory, Peking University First Hospital, Beijing, 100034, China.
J Neurol Sci. 2010 Apr 15;291(1-2):17-21. doi: 10.1016/j.jns.2010.01.012. Epub 2010 Feb 9.
m.3243A>G mutation in mitochondrial DNA is the most common pathogenic point mutation, causing a variety of phenotypes. To further elucidate its clinical characteristics, we recruited 47 Chinese families carrying m.3243A>G mutation and analyzed their symptoms, disease history, inheritance, and mitochondria-related complications. In the probands, lactic acidosis, myopathy, seizures, short stature, weight loss and hirsutism were the most common clinical features. In their mothers, lactic acidosis, exercise intolerance, short stature and weight loss were the frequent manifestations, and normal phenotype was found in 59.6% mothers. m.3243A>G mutation was detected in 47 probands and 42 mothers. In the probands, the mutation ratio in blood was threefold higher and the ratio in urine was twofold higher than those of their mothers. m.3243A>G mutation ratio in mothers' urine and in their probands' blood were weakly correlated. In conclusion, (a) stroke-like episode induced by m.3243A>G mutation may be the symptom predominantly found in older patients; (b) m.3243A>G mutation ratio correlates with the severity of the disease; (c) m.3243A>G mutation ratio in mothers' urine may correlate to the ratio in blood in their offspring.
线粒体 DNA m.3243A>G 突变是最常见的致病性点突变，可引起多种表型。为了进一步阐明其临床特征，我们招募了 47 个携带 m.3243A>G 突变的中国家庭，并分析了他们的症状、病史、遗传和与线粒体相关的并发症。在先证者中，乳酸性酸中毒、肌病、癫痫、身材矮小、体重减轻和多毛症是最常见的临床特征。在他们的母亲中，乳酸性酸中毒、运动不耐受、身材矮小和体重减轻是常见的表现，59.6%的母亲表现为正常表型。在 47 个先证者和 42 个母亲中检测到 m.3243A>G 突变。在先证者中，突变在血液中的比例是母亲的三倍，在尿液中的比例是母亲的两倍。母亲尿液中和先证者血液中 m.3243A>G 突变的比例呈弱相关。总之：（a）m.3243A>G 突变引起的中风样发作可能是老年患者的主要表现；（b）m.3243A>G 突变比例与疾病的严重程度相关；（c）母亲尿液中的 m.3243A>G 突变比例可能与后代血液中的比例相关。
