Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Pediatr Neurol. 2010 Jul;43(1):35-40. doi: 10.1016/j.pediatrneurol.2010.02.018.
Rett syndrome is a neurodevelopmental disorder caused by mutations in the methyl CpG binding protein 2 gene (MECP2). The MECP2 protein is expressed primarily in neurons, and mutations in the gene lead to the clinical features of Rett syndrome in human patients and neurologic deficits in murine models. Visual function is relatively preserved in Rett syndrome patients, but the cause is unknown. The eyes of two Rett syndrome patients who died of the disease were analyzed; no gross or microscopic changes were found. MECP2 expression was examined using immunohistochemistry; nuclear protein expression was largely limited to ganglion cells and the portion of the inner nuclear layer populated by amacrine cells. No significant differences in MECP2 protein level or distribution were identified in the two eyes from the Rett syndrome patients, compared with 11 controls. The findings were compared with MECP2 expression in the brain of these two subjects and in MECP2-deficient mice. The findings suggest that the normally limited expression of MECP2 in visual pathway neurons may underlie the intact vision observed in Rett syndrome.
雷特综合征是一种由甲基化CpG 结合蛋白 2 基因（MECP2）突变引起的神经发育障碍。MECP2 蛋白主要在神经元中表达，该基因的突变导致人类患者出现雷特综合征的临床特征和鼠模型中的神经功能缺陷。雷特综合征患者的视觉功能相对保留，但原因不明。对两名死于该病的雷特综合征患者的眼睛进行了分析；未发现明显的肉眼或显微镜下的改变。使用免疫组织化学检查 MECP2 的表达；核蛋白表达主要局限于神经节细胞和由无长突细胞组成的内核层部分。与 11 名对照相比，两名雷特综合征患者的眼睛中 MECP2 蛋白水平或分布没有明显差异。将这些发现与这两名患者的大脑中 MECP2 的表达和 MECP2 缺陷型小鼠进行了比较。这些发现表明，视觉通路神经元中 MECP2 的正常有限表达可能是雷特综合征中观察到的完整视力的基础。
