Abstract
Multiplex ligation-dependent probe amplification (MLPA) has been widely used to identify copy-number variations (CNVs), but MLPA’s sensitivity and specificity in mosaic CNV detection are largely unknown. Here, we present two mosaic deletions identified by MLPA as NF1 deletion of exons 17–21 and NF2 deletion of exons 9–10. Through cDNA analysis, genomic breakpoint-spanning PCR and Sanger sequencing, we found however both NF1 and NF2 deletions are each composed of two consecutive deletions, which cannot be differentiated by MLPA. Importantly, these consecutive deletions are most likely originating from a single genomic rearrangement and have been preserved independently in different populations of cells.
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Acknowledgements
This work was supported through internal funds from the Medical Genomics Laboratory at the University of Alabama at Birmingham (UAB).
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This study was approved by the UAB institutional review board. A waiver of informed consent and patient authorization has been obtained for this study.
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Hsiao, MC., Piotrowski, A., Poplawski, A.B. et al. Alternative outcomes of pathogenic complex somatic structural variations in the genomes of NF1 and NF2 patients. Neurogenetics 18, 169–174 (2017). https://doi.org/10.1007/s10048-017-0512-x
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DOI: https://doi.org/10.1007/s10048-017-0512-x