Abstract:
Rett syndrome (RTT) is a rare X-linked syndrome that predominantly affects girls. It is characterized by a severe and progressive neurodevelopmental disorder with neurological regression and autism spectrum features. The Rett syndrome is associated with a broad phenotypic spectrum. It ranges from a classical Rett syndrome defined by well-established criteria to atypical cases with symptoms similar to other syndromes, such as Angelman syndrome. The first case of a Moroccan female child carrying a R306X mutation in the MECP2 (Methyl-CpG-Binding Protein 2) gene, with an unusual manifestation of Rett syndrome, is presented here. She showed autistic regression, behavioral stagnation, epilepsy, unmotivated laughter, and craniofacial dysmorphia. Whole exome sequencing revealed a nonsense mutation (R306X), resulting in a truncated, nonfunctional MECP2 protein. The overlapping phenotypic spectrums between Rett and Angelman syndromes have been described, and an interaction between the MECP2 gene and the UBE3A (Ubiquitin Protein Ligase E3A) gene pathways is possible but has not yet been proven. An extensive genetic analysis is highly recommended in atypical cases to ensure an accurate diagnosis and to improve patient management and genetic counseling.
摘要:
Rett综合征(RTT)是一种罕见的X连锁综合征,主要影响女孩。它的特征是严重和进行性神经发育障碍,具有神经退化和自闭症谱系特征。Rett综合征与广泛的表型谱有关。它的范围从由公认的标准定义的经典Rett综合征到症状与其他综合征相似的非典型病例。比如Angelman综合征.第一例摩洛哥女性儿童在MECP2(甲基-CpG-结合蛋白2)基因中携带R306X突变,有一种不寻常的Rett综合征,在这里呈现。她表现出自闭症消退,行为停滞,癫痫,没有动机的笑声,和颅面畸形。全外显子组测序显示无义突变(R306X),导致截断,非功能性MECP2蛋白。已经描述了Rett和Angelman综合征之间的重叠表型谱,MECP2基因与UBE3A(泛素蛋白连接酶E3A)基因途径之间的相互作用是可能的,但尚未得到证实。强烈建议在非典型病例中进行广泛的遗传分析,以确保准确的诊断并改善患者管理和遗传咨询。