Clin Neuropathol. 2022 Nov-Dec;41(6):245-252. doi: 10.5414/NP301460.
The early growth response 2 gene mutations are associated with a group of hereditary neuropathy, including axonal neuropathy and hypomyelinating neuropathy or Charcot-Marie-Tooth disease (CMT) type 1D. We aim to perform an electrodiagnostic, nerve imaging, and histological study of EGR2-associated neuropathy.
We performed a retrospective analysis of two patients with EGR2-related neurology at our hospital. The neuropathy was confirmed by the nerve conduction study. Nerve imaging and sural biopsies were performed in two patients.
Two unrelated boys exhibited early-onset length-dependent neuropathy. Next generation sequencing identified gene with previously described E412K mutation in the third zine finger domain in patient 1 and a previously undescribed variant D355N mutation in the first zinc finger domain in patient 2. The magnetic resonance imaging of the lumbosacral plexus showed no abnormalities in patient 1 and thickened lumbosacral plexuses in patient 2. Electrophysiology and nerve biopsies showed a prominent axonal neuropathy, accompanied with demyelinating involvement.
Therefore, it seemed that the mutations could cause not only the known demyelinating type and axonal type but also mixed-type CMT. Our findings expanded the phenotypic heterogeneities of EGR2-associated neuropathy.
早期生长反应 2 基因 突变与一组遗传性神经病有关，包括轴索神经病和脱髓鞘性神经病或腓骨肌萎缩症（CMT）1D 型。我们旨在对 EGR2 相关神经病进行电诊断、神经影像学和组织学研究。
我们对我院 2 例 EGR2 相关神经病患者进行了回顾性分析。神经病通过神经传导研究得到证实。对 2 例患者进行了神经影像学和腓肠神经活检。
2 例无血缘关系的男孩均表现为早发性长度依赖性神经病。下一代测序在患者 1 中发现了第 3 锌指域中先前描述的 E412K 突变，在患者 2 中发现了第一个锌指域中先前未描述的 D355N 突变。腰骶丛磁共振成像显示患者 1 无异常，患者 2 腰骶丛增厚。电生理学和神经活检显示明显的轴索神经病，伴有脱髓鞘受累。
因此，这些 突变似乎不仅能引起已知的脱髓鞘型和轴索型，还能引起混合型 CMT。我们的发现扩展了 EGR2 相关神经病的表型异质性。
