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Licensed Unlicensed Requires Authentication Published by De Gruyter June 22, 2021

SLC35A2-CDG: novel variants with two ends of the spectrum

  • Çiğdem Seher Kasapkara EMAIL logo , Ahmet Cevdet Ceylan , Hamit Özyürek , Gülhan Karakaya Molla , Burcu Civelek Ürey , Oya Kıreker Köylü ORCID logo , Aynur Küçükçongar Yavaş and Fatma Müjgan Sönmez

Abstract

Objectives

Congenital disorders of glycosylation (CDGs) are rare inherited metabolic disorders associated with facial dysmorphism and in the majority of the patients, there is an important neurological impairment. Epilepsy was a main concern in rare forms of the disease. There are two groups of the disease: CDG-I results from the defects in glycan addition to the N-terminal and CDG-II occurs due to defects in the processing of protein bound glycans. SLC35A2-CDG is a rare form of CDG caused by mutations in the X-linked gene that encodes a UDP-Galactose transporter. The manifestations of the disease include seizures, failure to thrive, delayed myelination, and cerebral atrophy.

Case presentation

We describe herein a severe female child with intractable seizures, microcephaly, growth retardation, hypotonia, global developmental delay, facial dysmorphism, skeletal findings, cerebral/cerebellar atrophy, and thin corpus callosum, and a mildly affected male carrying a novel variant with seizures and mild global developmental delay who were found by whole exome sequencing (WES) for SLC35A2 mutations previously not reported.

Conclusions

Our findings expand the number of reported cases and add novel variants to the repertoire of SLC35A2-CDG.


Corresponding author: Ass. Prof. Dr. Çiğdem Seher Kasapkara, Department of Pediatric Metabolism, Ankara City Hospital, Ankara Yıldırım Beyazıt University, Ankara, Turkey, E-mail:

  1. Research funding: None declared.

  2. Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.

  3. Competing interests: Authors state no conflict of interest.

  4. Informed consent: Informed consent was obtained from all individuals included in this study.

  5. Ethical approval: The local Institutional Review Board deemed the study exempt from review.

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Received: 2021-04-27
Accepted: 2021-05-25
Published Online: 2021-06-22
Published in Print: 2021-09-27

© 2021 Walter de Gruyter GmbH, Berlin/Boston

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