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
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Weitere Informationen

Publikationsverlauf

19. Mai 2019

13. Juni 2019

Publikationsdatum:
30. Juli 2019 (online)

Abstract

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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