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Trisomy 16 is the most common type of autosomal trisomy associated with spontaneous abortion and is incompatible with life. Upon examining previously reported cases of partial chromosome 16q duplication, it was noted that the majority of cases had complex chromosomal abnormalities due to parental balanced chromosomal translocation carriage. The clinical presentation of very rare pure partial trisomy 16q cases was associated with congenital anomalies, facial dysmorphic findings and intellectual disability. In this study, we evaluated the physical characteristics and genetic data of an 8-month-old girl with developmental delay and facial dysmorphic features. Dysmorphic features including prominent metopic suture, synophrys, asymmetric head shape, triangular and asymmetric face, telecanthus, epicanthal folds, down-slanting palpebral fissures, microphthalmia of the left eye, anteverted nares, smooth and tented philtrum, microretrognathia, low-set posteriorly rotated ears, auricular pits, high-arched palate, thin upper lip and hypotonia were recorded. Her karyotype was 46,XX,add(16)(q24). To identify the extension of the duplicated section, array comparative genomic hybridization (aCGH) analysis was performed, which showed a de novo 29.8 Mb duplication [arr[hgl9] 16q12.1q23.3(52459169-82285105) x 3], interpreted to be pathogenic. We present this case report to clarify the clinical findings of a rare chromosomal anomaly, discuss the genes that may be related to the phenotype and advance the literature in terms of knowledge regarding genotypephenotype correlation.

Objective: To present the prenatal diagnosis and molecular cytogenetic characterization of a de novo unbalanced reciprocal translocation. Case Report: A 37-year-old woman, G3P1, underwent amniocentesis at 17 weeks of gestation because of her advanced maternal age. Her husband was 38 years old. Amniocentesis revealed a derivative chromosome 3 with the deletion of terminal 3p and the addendum of an unknown extra chromosomal segment on the distal 3p. The parental karyotypes were normal. Prenatal ultrasound findings were unremarkable. Array comparative genomic hybridization (aCGH) analysis using cultured amniocytes revealed a 2.38-Mb deletion in 3p26.3 [arr 3p26.3 (1-2,380,760)×1] encompassing 15 genes, which included 3 OMIM genes CHL1, CNTN6, and CNTN4, and a 13.17-Mb duplication in 16q23.1-q24.3 [arr 16q23.1q24.3 (76,999,082-90,170,596)×3] encompassing 207 genes, which included 81 OMIM genes. The pregnancy was subsequently terminated, and a malformed fetus was delivered with facial dysmorphism. Postnatal cord blood analysis revealed a karyotype of 46,XY,der(3)t(3;16)(p26.3;q23.1)dn. Polymorphic DNA marker analysis by quantitative fluorescent polymerase chain reaction (QF-PCR) on the DNAs extracted from the placenta and parental blood showed a paternal origin of the aberrant chromosome. Conclusion: The aCGH and QF-PCR analyses helped in delineating the genomic imbalance and parental origin of prenatally detected de novo unbalanced reciprocal translocation.

Objective: To present the prenatal diagnosis and molecular cytogenetic characterization of a de novo unbalanced reciprocal translocation., Case Report: A 37-year-old woman, G3P1, underwent amniocentesis at 17 weeks of gestation because of her advanced maternal age. Her husband was 38 years old. Amniocentesis revealed a derivative chromosome 3 with the deletion of terminal 3p and the addendum of an unknown extra chromosomal segment on the distal 3p. The parental karyotypes were normal. Prenatal ultrasound findings were unremarkable. Array comparative genomic hybridization (aCGH) analysis using cultured amniocytes revealed a 2.38-Mb deletion in 3p26.3 [arr 3p26.3 (1-2,380,760)×1] encompassing 15 genes, which included 3 OMIM genes CHL1, CNTN6, and CNTN4, and a 13.17-Mb duplication in 16q23.1-q24.3 [arr 16q23.1q24.3 (76,999,082-90,170,596)×3] encompassing 207 genes, which included 81 OMIM genes. The pregnancy was subsequently terminated, and a malformed fetus was delivered with facial dysmorphism. Postnatal cord blood analysis revealed a karyotype of 46,XY,der(3)t(3;16)(p26.3;q23.1)dn. Polymorphic DNA marker analysis by quantitative fluorescent polymerase chain reaction (QF-PCR) on the DNAs extracted from the placenta and parental blood showed a paternal origin of the aberrant chromosome., Conclusion: The aCGH and QF-PCR analyses helped in delineating the genomic imbalance and parental origin of prenatally detected de novo unbalanced reciprocal translocation., (Copyright © 2016. Published by Elsevier B.V.)