Abstract
Patients with terminal deletions of chromosome 6q present with structural brain abnormalities including agenesis of corpus callosum, hydrocephalus, periventricular nodular heterotopia, and cerebellar malformations. The 6q27 region harbors genes that are important for the normal development of brain and delineation of a critical deletion region for structural brain abnormalities may lead to a better genotype–phenotype correlation. We conducted a detailed clinical and molecular characterization of seven unrelated patients with deletions involving chromosome 6q27. All patients had structural brain abnormalities. Using array comparative genomic hybridization, we mapped the size, extent, and genomic content of these deletions. The smallest region of overlap spans 1.7 Mb and contains DLL1, THBS2, PHF10, and C6orf70 (ERMARD) that are plausible candidates for the causation of structural brain abnormalities. Our study reiterates the importance of 6q27 region in normal development of brain and helps identify putative genes in causation of structural brain anomalies.
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Acknowledgements
We thank all the patients and their family members for their cooperation and participation in this research study. We also thank all the research coordinators at BCM-MGL for their assistance in obtaining clinical information. This work was supported in part by fellowship grants by the Clinical Scientist Development Award from The Doris Duke Charitable Foundation (SNSC), DK081735-01A1, NIH /NIGMS T32 contract grant number GM07526 (AE).
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Peddibhotla, S., Nagamani, S., Erez, A. et al. Delineation of candidate genes responsible for structural brain abnormalities in patients with terminal deletions of chromosome 6q27. Eur J Hum Genet 23, 54–60 (2015). https://doi.org/10.1038/ejhg.2014.51
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DOI: https://doi.org/10.1038/ejhg.2014.51
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