Dobre Maria, Gaina Gisela, Erbescu Alina, Glangher Adelina, Linca Florentina Ionela, Ioana Doina, Severin Emilia Maria, Rad Florina, Iliescu Mihaela Catrinel, Papuc Sorina Mihaela, Hinescu Mihail Eugen, Arghir Aurora, Budișteanu Magdalena
Victor Babes National Institute of Pathology, 050096 Bucharest, Romania.
Faculty of Medicine, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania.
Genes (Basel). 2025 Jul 29;16(8):903. doi: 10.3390/genes16080903.
BACKGROUND/OBJECTIVES: Autism spectrum disorders (ASDs) are neurodevelopmental conditions with early onset of clinical manifestations. ASD etiology is highly heterogeneous, with genetic factors being strong determinants of the behavioral problems and neurodevelopmental deficits. Fragile X syndrome (FXS) (OMIM #300624), caused by the transcriptional silencing of the gene, represents the most common monogenic cause of autism. Our study included 226 boys with a diagnosis of ASD, for a systematic screening of genetic and epigenetic defects in the gene promoter in a Romanian pediatric cohort.
The methods, methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) and triplet-primed PCR (TP-PCR)/melt curve analysis (MCA), were chosen for their ability to detect the methylation anomalies (the former) as well as repeat expansions in the promoter (the latter).
Both methods used in our screening generated concordant results, detecting full mutation in 4 out of 226 patients (~1.8%). This yield is similar to data obtained in larger studies. Three out of four boys presented the typical clinical features, in correlation with genetic findings.
The combined use of MS-MLPA and TP-PCR/MCA-based assay was, in our experience, useful to fully describe the genetic defects responsible for FXS. A significant variability of clinical presentations was observed in our small group of children with FXS, from mild to severe intellectual disability and from atypical to characteristic dysmorphic features, as well as various behavioral problems.
背景/目的：自闭症谱系障碍（ASD）是一种临床表现早发的神经发育疾病。ASD的病因高度异质性，遗传因素是行为问题和神经发育缺陷的重要决定因素。脆性X综合征（FXS）（OMIM #300624）由该基因的转录沉默引起，是自闭症最常见的单基因病因。我们的研究纳入了226名诊断为ASD的男孩，对罗马尼亚儿科队列中该基因启动子的遗传和表观遗传缺陷进行系统筛查。
选择甲基化特异性多重连接依赖探针扩增（MS-MLPA）和三联体引物PCR（TP-PCR）/熔解曲线分析（MCA）方法，因其能够检测甲基化异常（前者）以及启动子中的重复扩增（后者）。
我们筛查中使用的两种方法产生了一致的结果，在226名患者中有4名（约1.8%）检测到该基因完全突变。这一结果与更大规模研究获得的数据相似。四名男孩中有三名表现出典型的临床特征，与基因检测结果相关。
根据我们的经验，联合使用MS-MLPA和基于TP-PCR/MCA的检测方法有助于全面描述导致FXS的遗传缺陷。在我们这一小群FXS患儿中观察到临床表现存在显著差异，从轻度到重度智力残疾，从非典型到典型的畸形特征，以及各种行为问题。
