Xu Jia-Lu, Zhang Yi, Zhao Cong-Ying, Jiang Pei-Fang, Yuan Zhe-Feng, Yu Yong-Lin, Xia Zhe-Zhi, Gao Feng
Department of Neurology, Children's Hospital of Zhejiang University School of Medicine, Hangzhou 310052, China.
Zhongguo Dang Dai Er Ke Za Zhi. 2019 Jul;21(7):670-675. doi: 10.7499/j.issn.1008-8830.2019.07.010.
To study the clinical characteristics and genetic variation of early-onset Charcot-Marie-Tooth disease (CMT).
Children with a clinical diagnosis of early-onset CMT were selected for the study. Relevant clinical data were collected, and electromyogram and CMT-related gene detection were performed and analyzed.
A total of 13 cases of early-onset CMT were enrolled, including 9 males (69%) and 4 females (31%). The mean age at consultation was 4.0±2.1 years. Among them, 12 children (92%) had an age of onset less than 2 years, 9 children (69%) were diagnosed with CMT type 1 (including 6 cases of Dejerine-Sottas syndrome), 1 child (8%) with intermediate form of CMT, and 3 children (23%) with CMT type 2. The genetic test results of these 13 children showed 6 cases (46%) of PMP22 duplication mutation, 3 cases (23%) of MPZ gene insertion mutation and point mutation, 3 cases (23%) of MFN2 gene point mutation, and 1 case (8%) of NEFL gene point mutation. Eleven cases (85%) carried known pathogenic mutations and 2 cases (15%) had novel mutations. The new variant c.394C>G (p.P132A) of the MPZ gene was rated as "possibly pathogenic" and the new variant c.326A>G (p.K109R) of the MFN2 gene was rated as "pathogenic".
Early-onset CMT is mainly caused by PMP22 gene duplication mutation and MPZ gene mutations. The clinical phenotype is mainly CMT type 1, among which Dejerine-Sottas syndrome accounts for a considerable proportion.
研究早发型夏科-马里-图斯病（CMT）的临床特征及基因变异情况。
选取临床诊断为早发型CMT的患儿进行研究。收集相关临床资料，并进行肌电图及CMT相关基因检测与分析。
共纳入13例早发型CMT患儿，其中男性9例（69%），女性4例（31%）。就诊时平均年龄为4.0±2.1岁。其中，12例患儿（92%）起病年龄小于2岁，9例患儿（69%）诊断为1型CMT（包括6例德热里纳-索塔斯综合征），1例患儿（8%）为CMT中间型，3例患儿（23%）为2型CMT。这13例患儿的基因检测结果显示，6例（46%）存在PMP22重复突变，3例（23%）存在MPZ基因插入突变及点突变，3例（23%）存在MFN2基因点突变，1例（8%）存在NEFL基因点突变。11例（85%）携带已知致病突变，2例（15%）存在新突变。MPZ基因的新变异c.394C>G（p.P132A）被评为“可能致病”，MFN2基因的新变异c.326A>G（p.K109R）被评为“致病”。
早发型CMT主要由PMP22基因重复突变及MPZ基因突变引起。临床表型以1型CMT为主，其中德热里纳-索塔斯综合征占相当比例。
