Characterization of mosaic supernumerary ring chromosomes by array-CGH: Segmental aneusomy for proximal 4q in a child with tall stature and obesity

• Published in: American journal of medical genetics. Part A 2006-02, Vol.140A (3), p.233-237
• Main Authors: Bonnet, Céline, Zix, Christian, Grégoire, Marie-José, Brochet, Karène, Duc, Mireille, Rousselet, Florence, Philippe, Christophe, Jonveaux, Philippe
• Format: Article
• Language: English
• Subjects: Abnormalities, Multiple - genetics; Abnormalities, Multiple - pathology; array-CGH; Biological and medical sciences; Child; chromosome 4; Chromosome Banding; Chromosomes, Human, Pair 4 - genetics; Developmental Disabilities - pathology; Family Health; Female; Genome, Human; Growth Disorders - pathology; Humans; IGFBP7; In Situ Hybridization, Fluorescence; Insulin-Like Growth Factor Binding Proteins - genetics; Karyotyping; Medical sciences; Metabolic diseases; Mosaicism; Nucleic Acid Hybridization - methods; Obesity; Obesity - pathology; overgrowth; Ring Chromosomes
• ISSN: 1552-4825; 1552-4833
• DOI: 10.1002/ajmg.a.31075

We report on a 6‐year‐old girl with developmental delay, tall stature, and obesity. G‐banded chromosome analysis revealed mosaicism for one to three small de novo rings in 82% of peripheral lymphocytes. Fluorescence in situ hybridization (FISH) studies and metaphase comparative genomic hybridization (CGH) demonstrated that the rings were derived from 4q10‐4q13. A higher resolution investigation was initiated using array‐CGH analysis and revealed a gain of 11 adjacent clones spanning a 16 Mb region at 4q11‐q13.2 and including the insulin‐like growth factor binding protein 7 (IGFBP7) gene. This finding suggests that postnatal overgrowth observed in our patient might be related to a dosage effect of the IGFBP7 gene. © 2006 Wiley‐Liss, Inc.