Wiedemann-Steiner syndrome (WWS) is a rare disorder characterized by hypotonia, postnatal growth restriction, striking facial dysmorphism, and hirsutism. It is caused by heterozygous pathogenic variants in KMT2A. This gene has an established role in histone methylation, which explains the overlap of WWS with syndromes caused by genes involved in chromatin remodeling. We describe an infant with a novel single base pair deletion in KMT2A with features consistent with WWS, as well as additional features of stenosis of aqueduct of Sylvius and broad toes. The usefulness of Face2Gene as a tool for identification of dysmorphology syndromes is discussed, as in this patient, it suggested WWS as the top candidate disorder. To the best of our knowledge, this is the first patient of WWS reported from India, with a novel genotype and expanded phenotype.

中文翻译：

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扩大Wiedemann-Steiner综合征的表型和基因型谱：来自印度的第一位患者。

Wiedemann-Steiner综合征（WWS）是一种罕见的疾病，其特征在于肌张力低下，产后生长受限，面部畸形和多毛症。它是由KMT2A中的杂合致病性变异引起的。该基因在组蛋白甲基化中具有确定的作用，这解释了WWS与由染色质重塑相关基因引起的综合症的重叠。我们描述了一种婴儿，其在KMT2A中具有新颖的单碱基对缺失，其特征与WWS一致，以及西尔维斯输水管和宽脚趾狭窄的其他特征。讨论了Face2Gene作为识别畸形综合征的工具的有用性，因为在该患者中，它提示WWS是最主要的候选疾病。据我们所知，这是印度报道的第一例WWS患者，具有新颖的基因型和扩展的表型。