To enhance the diagnosis, management, and monitoring of Chinese children with chromosome 15q11-q13 duplication syndrome (dup15q) by analyzing their genetic and clinical characteristics. In this study, one Chinese prenatal case and 21 postnatal cases genetically diagnosed with dup15q syndrome underwent a detailed assessment of genetic and clinical characteristics. Most patients had normal prenatal (12/22, 54.5%) and neonatal (14/21, 66.7%) histories. Most symptoms were developmental delays (motor: 18/21, 85.7%; cognition: 13/21, 61.9%; language: 12/21, 57.1%). Other common features included autism spectrum disorder (ASD)-related behaviors (10/21, 47.6%) and seizures (7/21, 33.3%). Trisomy microduplications accounted for 54.5% (12/22), and tetrasomy microduplications accounted for 40.9% (9/22) of cases. We compared the phenotypic differences between the two groups using a composite score. One rare case of paternal duplication presented with early-onset obesity and tapered fingers resembling Prader-Willi syndrome (PWS). In addition, non-invasive prenatal testing (NIPT) detected int dup(15) in prenatal cases. Some patients with epilepsy were well controlled without anti-seizure drugs or monotherapy (3/7, 42.8%), while others had refractory epilepsy. Chinese children with dup15q exhibited high clinical heterogeneity, including multisystem developmental delays, ASD-related symptoms, and seizures. Phenotypic severity is influenced by multiple factors. NIPT may show positive findings, and chromosomal microarray analysis (CMA) combined with methylation analysis is important.
Liu et al. (Mon,) studied this question.