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Identification of a novel homozygous UNC80 variant in a child with infantile hypotonia with psychomotor retardation and characteristic facies-2 (IHPRF2)

Abstract

The UNC80 gene encodes for a large component of the NALCN sodium-leak channel complex that regulates the basal excitability of the nervous system. In this study, we report on a novel homozygous mutation in UNC80 in a Palestinian-Emirati patient suffering infantile hypotonia with psychomotor retardation and characteristic facies. This mutation was detected by whole exome sequencing and confirmed using Sanger sequencing in the patient-parents trio. Numerous elements in the patient’s phenotype were in agreement with the few reported cases of UNC80 mutations; however there are some notable differences. We present comprehensive clinical and molecular accounts of this mutation in addition to a full review of previously reported patients of UNC80 mutations.

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Acknowledgements

Authors would like to thank the patient and his family for full cooperation. Thanks also go to Dubai Health Authority and Sheikh Hamdan Bin Rashid Al Maktoum Award for Medical Sciences for continuous and comprehensive support.

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Correspondence to Tasneem Obeid.

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This study was granted ethical approval for full compliance with the Code of Ethics of the Dubai Health Authority in the United Arab Emirates. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The guardian (parent) of the patient consented to both participation and publication of the case.

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Obeid, T., Hamzeh, A.R., Saif, F. et al. Identification of a novel homozygous UNC80 variant in a child with infantile hypotonia with psychomotor retardation and characteristic facies-2 (IHPRF2). Metab Brain Dis 33, 869–873 (2018). https://doi.org/10.1007/s11011-018-0200-z

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Keywords

  • Psychomotor retardation
  • Intellectual disability
  • Epilepsy
  • UNC80 gene
  • Novel mutation
  • Emirati