Recurrent 17q23.2 microdeletion flanked by segmental duplications associated with heart defects and limb abnormalities

[original title] Identification of recurrent microdeletion on 17q23.2 flanked by segmental duplications associated with heart defects and limb abnormalities. Segmental duplications, are known to mediate non-allelic homologous recombination and have been suggested to be hotspots in chromosome evolution and human genomic instability. We report the identification by microarray-based comparative genomic hybridization (aCGH) of seven individuals with microdeletions of 17q23.1q23.2. The clinical information obtained from six individuals for whom medical records were available showed common features including mild to moderate developmental delay, postnatal growth retardation, eye anomalies, heart defects and hand/foot/limb abnormalities. The presence in the deletion region of TBX2 and TBX4, transcription factors belonging to a family of genes implicated in a variety of developmental pathways including those of heart and limb, suggests that these genes may play an important role in the phenotype of this emerging syndrome. aCGH control vs. patient, total of 7 patients Lowest normalized log2 ratio = patient 1: -1.99; patient 2: -1.87; patient 3: -2.16; patient 4: -2.11; patient 5: -1.974802452; patient 6: -2.23; patient 7: -1.36.