Here, we report a novel case of a male patient with a hemizygous missense variant in STAG2 (p.Tyr159His) resulting in Mullegama–Klein–Martinez syndrome (MKMS), a rare X-linked cohesinopathy. He shares distinct clinical features with a previously reported male patient carrying the STAG2 variant p.Tyr159Cys, suggesting that this phenotype is determined by the position of the mutation. Additionally, our patient exhibits symptoms not previously associated with MKMS, expanding the known clinical phenotype of this rare disease.

中文翻译：

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扩展男性患者中 Mullegama-Klein-Martinez 综合征的已知表型

在这里，我们报告了一名男性患者的新病例，该患者携带STAG2 (p.Tyr159His)半合子错义变异，导致 Mullegama-Klein-Martinez 综合征 (MKMS)，这是一种罕见的 X 连锁粘连病。他与之前报道的一名携带 STAG2 变异 p.Tyr159Cys 的男性患者具有明显的临床特征，表明这种表型是由突变的位置决定的。此外，我们的患者表现出以前与 MKMS 无关的症状，扩大了这种罕见疾病的已知临床表型。