SYN1 encodes synapsin I, which is a neuronal phosphoprotein involving in regulating axonogenesis and synaptogenesis. Variants in the gene have been associated with X-linked neurodevelopmental disorders in recent years. In the study, we reported two male patients with familial SYN1 variants related neurodevelopmental disorders from Asian population. Previously published cases with significant SYN1 variants from the literature were also included to analyze the phenotype and genotype of the disorder. Two maternally inherited SYN1 variants, including c.C1076A, p.T359K in proband A and c.C1444T, p. Q482X in proband B (NM_133499) were found, which have never been described in detail. Combining with our research, all reported probands were male in the condition, whose significant SYN1 variants were inherited from their asymptomatic or mild affected mother. Although the disorder encompasses three main clinical presentations: mental deficiency, easily controlled reflex seizure and behavior problems, patients’ clinical manifestations vary in genders and individuals, even in the same pedigree. We firstly reported two familial SYN1-related neurodevelopmental disorders in Asian pediatric patients. Gender and phenotype differences should be highly valued in the disorder.

中文翻译：

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亚洲儿童患者中与家族性 SYN1 变异相关的神经发育障碍


SYN1 编码突触蛋白 I，它是一种参与调节轴突发生和突触发生的神经元磷蛋白。近年来，该基因的变异与 X 连锁神经发育障碍有关。在这项研究中，我们报告了两名来自亚洲人群的患有家族性 SYN1 变异相关神经发育障碍的男性患者。还包括先前发表的文献中具有显着 SYN1 变异的病例，以分析该疾病的表型和基因型。两个母系遗传的 SYN1 变体，包括先证者 A 中的 c.C1076A、p.T359K 和 c.C1444T，p.11。先证者B（NM_133499）中发现了Q482X，但从未被详细描述过。结合我们的研究，所有报告的先证者均为男性，其显着的 SYN1 变异遗传自其无症状或轻度受影响的母亲。尽管该疾病包含三种主要临床表现：精神缺陷、易控制的反射性癫痫发作和行为问题，但即使同一家系，患者的临床表现也因性别和个体而异。我们首次报道了亚洲儿科患者的两种家族性 SYN1 相关神经发育障碍。在该疾病中应高度重视性别和表型差异。