A De Novo Xp11.23 Duplication in a Girl with a Severe Phenotype: Expanding the Clinical Spectrum

Abstract

The Xp11.22–p11.23 duplication syndrome was described in 2009 by Giorda et al and is characterized by intellectual disability, speech delay, and electroencephalography anomalies. We report a case of a 23-month-old girl who presented with epilepsy and global developmental delay and who had a small duplication at Xp11.23. The case we present here is the first case showing the clinical features of Xp11.22–p11.23 duplication syndrome only involving synovial sarcoma, X breakpoint (SSX) genes: SSX1, SSX3, SSX4, and SSX9. This case report contributes to an expanding clinical spectrum of Xp11.22–p11.23 duplication syndrome.