Metabolic Brain Disease

, Volume 33, Issue 3, pp 869–873 | Cite as

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

  • Tasneem Obeid
  • Abdul Rezzak Hamzeh
  • Fatima Saif
  • Pratibha Nair
  • Madiha Mohamed
  • Mahmoud Taleb Al-Ali
  • Fatma Bastaki
Original Article


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.


Psychomotor retardation Intellectual disability Epilepsy UNC80 gene Novel mutation Emirati 



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.

Compliance with ethical standards

Conflicts of interest


Ethical approval

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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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Applied Biology/ Biotechnology ProgramUniversity of Sharjah, College of SciencesSharjahUnited Arab Emirates
  2. 2.Centre for Arab Genomic StudiesDubaiUnited Arab Emirates
  3. 3.Pediatric Department, Latifa HospitalDubai Health AuthorityDubaiUnited Arab Emirates

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