J Pediatr Genet 2018; 07(01): 035-039
DOI: 10.1055/s-0037-1605592
Case Report
Georg Thieme Verlag KG Stuttgart · New York

Inheritance of a Balanced t(12;20)(q24.33;p12.2) and Unbalanced der(13)t(7;13)(p21.3;q33.2) from a Maternally Derived Double Balanced Translocation Carrier

Jess F. Peterson
Department of Pathology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
,
Gabrielle C. Geddes
Department of Pediatrics, Section of Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
,
Donald G. Basel
Department of Pediatrics, Section of Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
Human and Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
,
Dana Schippman
Department of Pediatrics, Section of Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
,
John W. Grignon Jr.
Wisconsin Diagnostic Laboratories, Milwaukee, Wisconsin, United States
,
Peter vanTuinen
Department of Pathology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
,
Ulrike P. Kappes
Human and Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
The Advanced Genomics Laboratory at Children's Research Institute, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
› Author Affiliations
Further Information

Publication History

21 June 2017

10 July 2017

Publication Date:
14 August 2017 (eFirst)

Abstract

We report a 4-month-old male proband with a history of prominent forehead, hypertelorism, ear abnormalities, micrognathia, hypospadias, and multiple cardiac abnormalities. Initial microarray analysis detected a concurrent 7p21.3-p22.3 duplication and 13q33.2-q34 deletion indicating an unbalanced rearrangement. However, subsequent conventional cytogenetic studies only revealed what appeared to be a balanced t(12;20)(q24.33;p12.2). Fluorescence in situ hybridization (FISH) using chromosome-specific subtelomere probes confirmed the presence of an unbalanced der(13)t(7;13)(p21.3;q33.2) and balanced t(12;20)(q24.33;p12.2), both of maternal origin. In addition to our unique clinical findings, this case highlights the benefits and limitations of both conventional cytogenetic studies and microarray analysis and how FISH complements each methodology.