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Journal of Pediatric Neurology 2022; 20(03): 224-226
DOI: 10.1055/s-0041-1732482
Case Report

Identification of a Homozygous Deletion within FGD4 in a Charcot-Marie-Tooth type 4H Family by Exome Sequencing

Coskun Yarar
1   Department of Pediatric Neurology, Faculty of Medicine, Eskisehir Osmangazi University, Eskisehir, Turkey
,
Hasan Bas 
2   Department of Medical Genetics, Faculty of Medicine, Eskisehir Osmangazi University, Eskisehir, Turkey
,
Gokalp Celik
3   Intergen Genetic Diagnosis Center, Ankara, Turkey
,
Oguz Cilingir
2   Department of Medical Genetics, Faculty of Medicine, Eskisehir Osmangazi University, Eskisehir, Turkey
,
Kursat Bora Carman
1   Department of Pediatric Neurology, Faculty of Medicine, Eskisehir Osmangazi University, Eskisehir, Turkey
,
Sevilhan Artan
2   Department of Medical Genetics, Faculty of Medicine, Eskisehir Osmangazi University, Eskisehir, Turkey
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Abstract

Charcot-Marie-Tooth (CMT) disease is a group of clinically and genetically heterogeneous peripheral neuropathies by causing distal muscle weakness, sensory impairment, hyporeflexia, and skeletal deformities. Both of sequence and copy number variations (CNVs) of over 80 genes have been described in CMT patients so far, and FGD4 variants are among the uncommon causes of the disease. In this article, we present four siblings with early-onset CMT, who were found to carry a novel homozygous deletion within FGD4 gene by exome sequencing. Since CNVs of CMT-related genes other than PMP22 have been rarely described in literature and they are prone to be overlooked by next generation sequencing, this report confirms the importance of paying additional attention to these variants to increase diagnostic yield in CMT.

Keywords

Charcot-Marie-Tooth - CMT4H - FGD4 - deletion - copy number variations

Supplementary Material



Publication History

Received: 08 April 2021

Accepted: 08 June 2021

Article published online:
23 July 2021

© 2021. Thieme. All rights reserved.

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