Emam Bayoumi A, Abdel-Hamid Mohamed S, Eid Maha, Girgis Marian, Ragab Omar A, Zaki Maha S, El-Kiki Hassan, Abdel-Hady Sawsan, Abdel-Salam Ghada M H
Department of Clinical Genetics, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt.
Medical Molecular Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt.
Mol Syndromol. 2024 Dec;15(6):474-480. doi: 10.1159/000539364. Epub 2024 Jun 20.
Pontocerebellar hypoplasia (PCH) represents a group of rare disorders with prenatal onset and time-dependent loss of brain parenchyma, predominantly affecting the cerebellum and pons with variable involvement of supratentorial structures. Radiologically and pathologically, they are characterized by small cerebellum and pons. Our study aimed to screen for the gene variants in Egyptian patients with PCH for proper counseling and to describe the brain MRI and the clinical phenotype and compare, them to those described in the literature.
Thirty patients from thirty Egyptian families with a diagnosis of PCH based on neuroimaging findings were selected. Clinical evaluation, radiological findings, and genetic investigations were done for all patients.
The common missense variant c.919G>T (p.A307S) was identified in only 6 patients from six unrelated families (6/30; 20%) who showed different degrees of pontocerebellar malformations on brain imaging.
The presence of a dragonfly/butterfly-like pattern in the coronal section of the cerebellum recommends genetic testing of as a first step. For negative cases, whole-exome sequencing is essential to reach a definite diagnosis and determine the etiology.
脑桥小脑发育不全(PCH)是一组罕见的疾病,始于产前,脑实质呈时间依赖性丧失,主要影响小脑和脑桥,幕上结构受累情况不一。在影像学和病理学上,其特征为小脑和脑桥体积小。我们的研究旨在筛查埃及PCH患者的基因变异,以便进行恰当的遗传咨询,并描述脑部MRI表现及临床表型,同时与文献中描述的情况进行比较。
基于神经影像学检查结果,从30个埃及家庭中选取了30例诊断为PCH的患者。对所有患者进行了临床评估、影像学检查及基因检测。
仅在来自6个无亲缘关系家庭的6例患者(6/30;20%)中发现了常见的错义变异c.919G>T(p.A307S),这些患者的脑部影像学检查显示出不同程度的脑桥小脑畸形。
小脑冠状切面出现蜻蜓/蝴蝶样形态提示应首先进行基因检测。对于检测结果为阴性的病例,全外显子测序对于明确诊断和确定病因至关重要。