A Case of Trisomy 13 Mosaicism Presenting with a Severe Aortic Root Dilatation and Marfanoid Habitus due to an Unpredictable Cytogenetic Mechanism

• Published in: Cytogenetic and genome research Vol. 160; no. 2; p. 72
• Main Authors: Monin, Pauline, Reynaud, Nicolas, Hanna, Nadine, Dupuis-Girod, Sophie, Till, Marianne, Arnaud, Pauline, Labalme, Audrey, Alix, Eudeline, Poizat-Amar, Coline, Faoucher, Marie, Ravella, Lucie, Debost, Bernard, Obadia, Jean-François, Zech, Jean-Christophe, Boileau, Catherine, Sanlaville, Damien, Edery, Patrick, Putoux, Audrey, Schluth-Bolard, Caroline
• Format: Journal Article
• Language: English
• Published: Switzerland 2020
• Subjects: Aorta - abnormalities; Chromosomes, Human, Pair 10 - genetics; Chromosomes, Human, Pair 13 - genetics; Comparative Genomic Hybridization; Humans; In Situ Hybridization, Fluorescence; Male; Marfan Syndrome - etiology; Mosaicism; Translocation, Genetic; Trisomy 13 Syndrome - diagnosis; Trisomy 13 Syndrome - genetics; Young Adult; Translocation; Mosaicism; Trisomy 13; Interstitial telomere; Bicuspid aortic valve
• ISSN: 1424-859X
• DOI: 10.1159/000506319

In this report, we present a new case of mosaic trisomy 13 with prolonged survival, firstly detected by array-CGH analysis which was carried out because of moderate intellectual disability with postaxial hexadactyly, dermatologic features, ventricular septal defect, bicuspid aortic valve, and aortic dystrophy in a 19-year-old male patient. In a subset of 15% of the cells, the patient carried a derivative chromosome 10 generated by a nonreciprocal (10;13) translocation inherited from his healthy mother who carried the translocation in a balanced and homogeneous state. FISH analyses showed interstitial telomeric sequences at the breakpoints. To our knowledge, this is the second report of a patient with trisomy 13 mosaicism displaying a severe aortic root dilatation. We also discuss the mechanisms which could explain the mosaic state, the most likely one being related to the instability of the interstitial telomere.