We report the case of a hydrocephalic fetus in which clinical exome sequencing revealed a recurrent synonymous variant of unknown significance, c.453G>T, in the L1CAM gene. This report presents the second case of X-linked hydrocephalus in a fetus with this variant. Since we reproduced the RNA analysis, we were able to reclassify this variant as likely pathogenic. Our results stress the importance of not excluding synonymous variants during prioritization.

中文翻译：

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脑积水胎儿中反复出现的同义 L1CAM 变异

我们报告了一个脑积水胎儿的病例，其中临床外显子组测序显示L1CAM基因中存在意义不明的反复同义变异，即 c.453G>T。本报告介绍了第二例患有该变异胎儿的 X 连锁脑积水病例。由于我们重复了 RNA 分析，我们能够将这种变异重新分类为可能致病的。我们的结果强调了在优先级排序期间不排除同义变体的重要性。