Abstract
Interstitial deletions of 6q are rare. We report a detailed clinical and molecular characterization of four patients with interstitial deletion involving 6q25. All of our patients presented with microcephaly, developmental delay, dysmorphic features and hearing loss, whereas two of them had agenesis of the corpus callosum. We determined the size, extent and genomic content of the deletions using high-density array-comparative genomic hybridization (a-CGH), and found that a common segment spanning 3.52 Mb within the 6q25.2–q25.3 region was deleted in all four cases. We hypothesize that a subset of genes in the commonly deleted region are dosage sensitive and that haploinsufficieny of these genes impairs normal development of the brain and hearing.
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Acknowledgements
We thank the participating families for their kind cooperation. This work was supported in part by fellowship grants from the Osteogenesis Imperfecta Foundation (SNSC) and the National Urea Cycle Foundation and Children's National Medical Center (AE).
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Nagamani, S., Erez, A., Eng, C. et al. Interstitial deletion of 6q25.2–q25.3: a novel microdeletion syndrome associated with microcephaly, developmental delay, dysmorphic features and hearing loss. Eur J Hum Genet 17, 573–581 (2009). https://doi.org/10.1038/ejhg.2008.220
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DOI: https://doi.org/10.1038/ejhg.2008.220
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