J Pediatr Genet 2019; 08(04): 252-256
DOI: 10.1055/s-0039-1693664
Case Report
Georg Thieme Verlag KG Stuttgart · New York

Further Delineation of the TRAPPC6B Disorder: Report on a New Family and Review

Pratibha Nair
1   Centre for Arab Genomic Studies, Dubai, UAE
Lara El-Bazzal
2   Aix Marseille University, Inserm, Marseille Medical Genetics
Hicham Mansour
(MMG), U 1251, Marseille, France
Sandra Sabbagh
3   Department of Pediatrics, Saint George Hospital, Beirut, Lebanon
Mahmoud Taleb Al-Ali
1   Centre for Arab Genomic Studies, Dubai, UAE
Alicia Gambarini
4   Department of Pediatrics, Hotel-Dieu de France, Beirut, Lebanon
Valerie Delague
2   Aix Marseille University, Inserm, Marseille Medical Genetics
Stephany El-Hayek
1   Centre for Arab Genomic Studies, Dubai, UAE
4   Department of Pediatrics, Hotel-Dieu de France, Beirut, Lebanon
5   Institut Jérôme Lejeune, BioJeL Biological Resource Center (CRB BioJeL), Paris, France
› Author Affiliations
Further Information

Publication History

19 May 2019

13 June 2019

Publication Date:
30 July 2019 (online)


Pathogenic variants in the TRAPPC6B gene were recently found to be associated in three consanguineous families, with microcephaly, epilepsy, and brain malformations. Here, we report on a 3.5-year-old boy, born to consanguineous Lebanese parents, who presented with developmental delay, lactic acidosis, postnatal microcephaly, and abnormal brain magnetic resonance imaging. By whole exome sequencing, a novel homozygous likely pathogenic variant in exon 1 of the TRAPPC6B gene (c.23T > A; [p.Leu8*]) was identified. A review of the clinical description and literature is discussed, pointing out the phenotypic heterogeneity associated with mutations in this gene.

Ethical Approval

Informed and written consent was provided by the parents. The study protocol was approved by the institutional ethics committee and was in agreement with the guidelines of the Declaration of Helsinki.

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