MECP2重复综合征的临床表型及遗传学分析

Clinical phenotype and genetic analysis of MECP2 duplication syndrome

目的探讨MECP2重复综合征患者的临床症状及遗传学来源,为家系的遗传咨询及产前诊断提供依据。方法对2018年1月至2019年9月在郑州大学第一附属医院遗传与产前诊断中心接受基因组拷贝数变异测序技术(copy number variation sequencing,CNV-seq)检测且确诊为MECP2重复综合征的4例患者进行临床症状分析,并对其进行母源溯源。结果4例患者均为男性,其CNV-seq结果显示Xq28区域存在0.32〜0.86 Mb微重复,且均来自无症状的母亲。其中3例两倍拷贝数重复的患者存在语言能力缺失、智力低下、肌张力减退等症状;1例三倍拷贝数重复的患者在出生后6个月夭折,生前临床症状为反复感染、癫痫、痉挛等。结论4例MECP2重复综合征均为完全显性的男性患者,且遗传自无症状的母亲。CNV-Seq检测技术稳定、可靠,可准确地检测出MECP2重复综合征。

Objective To analyze the clinical symptom and parental origin of patients with MECP2 duplication syndrome in order to provide a basis for genetic counseling and prenatal diagnosis.Methods Clinical symptoms of four patients who were diagnosed with MECP2 duplication syndrome by copy number variation sequencing(CNV-Seq)were reviewed.The maternal origin of the duplications were verified.Results All patients were males,and CNV-Seq revealed that they have all harbored a duplication in the Xq28 region spanning 0.32〜0.86 Mb,which were derived from asymptomatic mothers.The clinical symptoms of three patients with three copies included delayed speech,intellectual disability,and muscular hypotonia,while the patient with four copies had died at 6 months after birth,with clinical symptoms including recurrent infections,seizures,and spasticity.Conclusion The four cases of MECP2 duplication syndrome have shown complete penetrance and have all derived from asymptomatic mothers.As a stable and reliable method,CNV-Seq can accurately detect the MECP2 duplication syndrome.