Abstract
Fragile X syndrome, the most common form of X-linked intellectual disability, results from transcriptional silencing of the FMR1 gene. As of yet, the phenotypic consequences of the duplication of FMR1 have not been well characterized. In this report, we characterize the clinical features in two females with duplications involving only the FMR1 gene. In addition, we describe the phenotypes of two subjects with deletion of FMR1 and show that both loss and gain of FMR1 copy number can lead to overlapping neurodevelopmental phenotypes. Our report supports the notion that FMR1 gene dosage is important for normal neurocognitive function.
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Acknowledgments
We thank the patients and their families for their kind cooperation. This work was supported in part by fellowship grants by the National Urea Cycle Disorders Foundation and LCRC from Osteogenesis Imperfecta Foundation (SNSC), DK081735-01A1, NIH /NIGMS T32 contract grant no. GM07526 (AE).
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Sandesh CS Nagamani and Ayelet Erez contributed equally to this work.
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Nagamani, S.C.S., Erez, A., Probst, F.J. et al. Small genomic rearrangements involving FMR1 support the importance of its gene dosage for normal neurocognitive function. Neurogenetics 13, 333–339 (2012). https://doi.org/10.1007/s10048-012-0340-y
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DOI: https://doi.org/10.1007/s10048-012-0340-y