腓骨肌萎缩症（Charcot—Marie—Tooth disease，CMT）又称为遗传性运动感觉神经病（hereditary motor and sensory neuropathies，HMSN），是一种最常见的遗传性周围神经病，患病率约为1／2500，具有高度的临床和遗传异质性。目前的研究热点主要集中在CMT的分子发病机制，其中线粒体作为细胞的重要细胞器，具有广泛的生理功能。
Objective: To investigate the Cx32 mutation features and the clinical manifestations of Chinese patients with Charcot-Marie-Tooth disease(CMT). Methods: Twenty-four of 65 unrelated CMT patients were selected for Cx32 mutation screening after the exclusion of the CMT1A 1.5 Mb duplication and male-to-male transmission. The motor and sensory nerve conduction studies were performed in all probands and most of their affected family members to establish the clinical CMT1 ,CMT2 or CMT intermediate diagnosis. The presence of mutations in the coding region of Cx32 was detected by single-strand conformation polymorphism analysis combined with direct sequencing. Results: We found 7 different point mutations in the coding region of Cx32 in a total of 7 families. All the patients were mildly to moderately affected with a clinical CMT1 or CMT intermediate diagnosis. The mutation Arg15Gln was inherited with X-linked recessive trait in family 1 involved in our study. The Arg75Trp mutation was detected in a family with X-linked dominant CMT and autosomal recessive nonsydromic hearing loss. The clinical phenotype of the Thr188Ala mutation was firstly reported. Conclusion: Seven different Cx32 point mutations were detected and the percentage of Chinese CMT families with Cx32 mutation is about 10% in our study. The inheritance model of CMT secondary to Cx32 mutation could be X-linked dominant, X-linked recessive or sporadic. Male patients are usually more severely affected than females with slower nerve conduction velocities. Cx32 mutation screening should be firstly performed in those CMT families without male-to-male transmission and CMT1A duplication.
