Bähr M, Andres F, Timmerman V, Nelis M E, Van Broeckhoven C, Dichgans J
Neurologische Universitätsklinik, Tübingen, Germany.
J Neurol Neurosurg Psychiatry. 1999 Feb;66(2):202-6. doi: 10.1136/jnnp.66.2.202.
X linked dominant Charcot-Marie-Tooth disease (CMT1X) is an inherited motor and sensory neuropathy that mainly affects the peripheral nervous system. CMT1X is associated with mutations in the gap junction protein connexin 32 (Cx32). Cx32 is expressed in Schwann cells and oligodendrocytes in the peripheral (PNS) and in the (CNS) respectively.
A CMT1X family with a Cx32 mutation was examined clinically and electrophysiologically to determine whether PNS, or CNS, or both pathways were affected.
In a CMT1X family a novel mutation (Asn205Ser) was found in the fourth transmembrane domain of Cx32. The patients showed typical clinical and electrophysiological abnormalities in the PNS, but in addition visual, acoustic, and motor pathways of the CNS were affected subclinically. This was indicated by pathological changes in visually evoked potentials (VEPs), brainstem auditory evoked potentials (BAEPs), and central motor evoked potentials (CMEPs).
These findings underscore the necessity of a careful analysis of CNS pathways in patients with CMT and Cx32 mutations. Abnormal electrophysiological findings in CNS pathway examinations should raise the suspicion of CMTX and a search for gene mutations towards Cx32 should be considered.
X连锁显性遗传性腓骨肌萎缩症（CMT1X）是一种主要影响周围神经系统的遗传性运动和感觉神经病变。CMT1X与缝隙连接蛋白连接蛋白32（Cx32）的突变有关。Cx32分别在外周神经系统（PNS）的施万细胞和中枢神经系统（CNS）的少突胶质细胞中表达。
对一个携带Cx32突变的CMT1X家系进行临床和电生理检查，以确定PNS、CNS或两者途径是否受到影响。
在一个CMT1X家系中，在Cx32的第四个跨膜结构域中发现了一个新的突变（Asn205Ser）。患者在PNS中表现出典型的临床和电生理异常，但此外，CNS的视觉、听觉和运动途径也受到亚临床影响。这通过视觉诱发电位（VEP）、脑干听觉诱发电位（BAEP）和中枢运动诱发电位（CMEP）的病理变化得以表明。
这些发现强调了对患有CMT和Cx32突变的患者仔细分析CNS途径的必要性。CNS途径检查中的异常电生理发现应引起对CMTX的怀疑，并应考虑寻找针对Cx32的基因突变。
