The guanine exchange factor subunit eEF1Bα encoded by the EEF1B2 gene belongs to the eukaryotic elongation translational machinery. Pathogen variants in genes of the translational machinery have been associated with several neurodevelopmental disorders. However, only one family of three siblings with intellectual disability (ID) has been reported so far with a homozygous variant in EEF1B2. Here, we report a second family with a novel homozygous loss of function (LoF) variant p.(Ser128*), carried by two siblings with moderate ID and seizures. Our findings confirm the role of EEF1B2 variants in the pathogenesis of autosomal‐recessive ID, expand the variant spectrum and precisely describe the clinical consequences of the LoF of EEF1B2.

中文翻译：

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EEF1B2基因双等位基因功能丧失导致智力障碍的新证据

EEF1B2基因编码的鸟嘌呤交换因子亚基eEF1Bα属于真核伸长翻译机器。翻译机器的基因中的病原体变异已与几种神经发育障碍有关。然而，到目前为止，据报道只有三个有智力障碍（ID）的兄弟姐妹家庭在EEF1B2中具有纯合子变体。在这里，我们报告第二个家族，其新的纯合功能丧失（LoF）变体p。（Ser128 *）由两个中等ID和癫痫发作的兄弟姐妹携带。我们的发现证实了EEF1B2变异体在常染色体隐性ID发病机理中的作用，扩展了变异体谱并精确描述了EEF1B2 LoF的临床后果。