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BMC Medical Genetics

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Open Access 01-12-2015 | Case report

MECP2 duplication syndrome in a Chinese family

Authors: Qingping Zhang, Ying Zhao, Yanling Yang, Xinhua Bao

Published in: BMC Medical Genetics | Issue 1/2015

Abstract

Background

Methyl-CpG-binding protein 2 (MeCP2) is a key transcriptional regulator of gene expression in the maintenance and development of the central nervous system. Loss- or gain-function of this gene may contribute to neurodevelopmental disorders. The aim of this study is to delineate the clinical characteristics of MECP2 duplication syndrome and the hereditary mechanism in a Chinese family.

Case presentation

We identified a Chinese family with three persons carry MECP2 gene duplication: a boy, his mother and his grandmother. The duplication segment which was detected by multiplex ligation-dependent probe amplification (MLPA) included gene MECP2, interleukin-1 receptor-associated kinase 1 (IRAK1), filamin A (FLNA), and L1 cell adhesion molecule (L1CAM). Furthermore, array comparative genomic hybridization (aCGH) was performed on the mother, showed that MECP2 containing duplication was 510 Kb (153,113,885-153,624,154), including 16 other genes except MECP2. The boy showed most symptoms of MECP2 duplication syndrome. His mother and maternal grandmother were asymptomatic. Both female carriers had a skewed X chromosome inactivation (XCI), which were 80:20 and 74:26 respectively.

Conclusion

To our knowledge, this is the second reported Chinese Han family with MECP2-containing duplications. And this patient had recurrent respiratory infections which was different from the first two Chinese-brother cases. MECP2 is the core gene responsible for MECP2 duplication syndrome. XCI may play an important role in modulating the clinical manifestation.

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Title: MECP2 duplication syndrome in a Chinese family
Authors: Qingping Zhang
Ying Zhao
Yanling Yang
Xinhua Bao
Publication date: 01-12-2015
Publisher: BioMed Central
Published in: BMC Medical Genetics / Issue 1/2015
Electronic ISSN: 1471-2350
DOI: https://doi.org/10.1186/s12881-015-0264-0

Keynote webinar | Spotlight on medication adherence

Springer Medicine

MECP2 duplication syndrome in a Chinese family

Abstract

Background

Case presentation

Conclusion

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Background

Case presentation

Conclusion

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