We aimed to detect the causative gene in five unrelated families with recessive inheritance pattern neurological disorders involving the central nervous system, and the potential function of the NEMF gene in the central nervous system. Exome sequencing (ES) was applied to all families and linkage analysis was performed on family 1. A minigene assay was used to validate the splicing effect of the relevant discovered variants. Immunofluorescence (IF) experiment was performed to investigate the role of the causative gene in neuron development. The large consanguineous family confirms the phenotype-causative relationship with homozygous frameshift variant (NM_004713.6:c.2618del) as revealed by ES. Linkage analysis of the family showed a significant single-point LOD of 4.5 locus. Through collaboration in GeneMatcher, four additional unrelated families’ likely pathogenic NEMF variants for a spectrum of central neurological disorders, two homozygous splice-site variants (NM_004713.6:c.574+1G>T and NM_004713.6:c.807-2A>C) and a homozygous frameshift variant (NM_004713.6: c.1234_1235insC) were subsequently identified and segregated with all affected individuals. We further revealed that knockdown (KD) of Nemf leads to impairment of axonal outgrowth and synapse development in cultured mouse primary cortical neurons. Our study demonstrates that disease-causing biallelic NEMF variants result in central nervous system impairment and other variable features. NEMF is an important player in mammalian neuron development.

我们的目的是检测 5 个患有涉及中枢神经系统的隐性遗传模式神经系统疾病的不相关家族的致病基因，以及NEMF基因在中枢神经系统中的潜在功能。对所有家族进行外显子组测序 (ES)，并对家族 1 进行连锁分析。使用小基因测定来验证相关发现变体的剪接效果。进行免疫荧光（IF）实验来研究致病基因在神经元发育中的作用。 ES 揭示的大型近亲家族证实了与纯合移码变异 (NM_004713.6:c.2618del) 的表型因果关系。该家族的连锁分析显示 4.5 位点的显着单点 LOD。通过 GeneMatcher 的合作，另外四个不相关家族的可能致病性 NEMF 变异导致一系列中枢神经系统疾病，两个纯合剪接位点变异 (NM_004713.6:c.574+1G>T 和 NM_004713.6:c.807-2A >C) 和纯合移码变体 (NM_004713.6: c.1234_1235insC) 随后被鉴定并与所有受影响的个体分离。我们进一步发现， Nemf的敲除（KD）会导致培养的小鼠原代皮质神经元的轴突生长和突触发育受损。我们的研究表明，致病的双等位基因NEMF变异会导致中枢神经系统损伤和其他可变特征。 NEMF在哺乳动物神经元发育中发挥着重要作用。