Prenatal diagnosis of an asymptomatic familial case with 21-Mb duplication of chromosome 11q14.1q22.3

Introduction: 11q partial trisomy is rare and associated with clinical features including growth restriction, developmental delays. Here, we describe an asymptomatic family with an interstitial 11q14q22 duplication ascertained at prenatal diagnosis. Case Presentation: A 33-year-old pregnant woman referred for positive fetal cell-free DNA screening. Chromosome karyotyping analysis was performed on amniotic fluid cells and 11q14q22 duplication was ascertained at prenatal diagnosis, which is also present in the fetus’s mother and maternal aunt with normal phenotype. Ultimately, the pregnancy outcome was favorable, and a healthy infant was delivered. Conclusion Single nucleotide polymorphism array analysis of amniotic fluid DNA confirmed a 21-Mb duplication of 11q14.1q22.3.The current case represents the first familial case of 11q interstitial duplications with normal development and provides genotype-phenotype reference for genetic counseling of 11q duplication. However, long-term postnatal follow-up is still required to monitor the child's neurodevelopment and growth