Case Report

Volume: 4 | Issue: 1 | Published: Jan 04, 2021 | Pages: 56 - 63 | DOI: 10.24911/JBCGenetics/183-1602852756

Congenital myasthenic syndrome type 23 caused by a missense homozygous c.205G>T (p.Asp69Tyr) in SLC25A1 gene in four Emirati patients from a single family


Authors: Aisha M. AlShamsi , Qudsia R. Shaukat , Mohammed H. AlKuwaiti


Article Info

Authors

Aisha M. AlShamsi

Tawam Hospital, Al Ain, United Arab Emirates

Qudsia R. Shaukat

Tawam Hospital, Al Ain, United Arab Emirates

Mohammed H. AlKuwaiti

Tawam Hospital, Al Ain, United Arab Emirates

Publication History

Received: October 16, 2020

Revised: November 26, 2020

Accepted: December 04, 2020

Published: January 04, 2021


Abstract


Background: Congenital myasthenic syndromes (CMSs) are a clinically and genetically heterogeneous group of disorders caused by mutations that lead to altered neuromuscular junction transmissions. Recently, the solute carrier family 25 member 1 (SLC25A1) gene was described to cause CMS type 23. This gene encodes a mitochondrial citrate carrier, associated mainly with a severe neurometabolic disease like combined D-2- and L-2-hydroxyglutaric aciduria (D/L-2-HGA). Case presentation: Here, we report four Emirati patients with a homozygous missense variant in SLC25A1 with a phenotype restricted to relatively mild CMS. We performed whole-exome sequencing (WES) in two relatives who presented with CMS to identify the underlying causative gene. Conclusion: The WES analysis revealed the presence of a homozygous c.205G>T (p.Asp69Tyr) [(c.226G>T (p.Asp76Tyr)] in the SLC25A1 gene; the same variant was identified in the other members in this family with the same phenotype. This suggests that c.205G>T (p.Asp69Tyr) [(c.226G>T p.(Asp76Tyr)] is associated with a relatively mild CMS phenotype and can be considered as a founder mutation in our region.

Keywords: Congenital myasthenic syndrome type 23, SLC25A1 gene, whole-exome sequencing