Genetic Analysis of Children with Dravet Syndrome in a Resourcelimited Setting

Authors

  • Sorawit Viravan Division of Neurology, Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
  • Chutima Meesamarnpong Division of Medical Genetics Research and Laboratory, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
  • Wanna Thongnoppakhun Division of Medical Genetics Research and Laboratory, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
  • Mongkol Chanvanichtrakool Division of Neurology, Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.

DOI:

https://doi.org/10.31584/jhsmr.2021838

Keywords:

Dravet syndrome, SCN1A, PCDH19, Thai children, Sanger sequencing

Abstract

Objective: To identify the common causal gene mutations in Thai children with the Dravet (DS) phenotype, using single gene analysis.

Material and Methods: The study was carried out on 20 DS patients at Siriraj Hospital, Bangkok, Thailand. Sanger sequencing of the Voltage-Gated Sodium Channel Alpha Subunit 1 (SCN1A) gene was conducted in all patients. In SCN1A-negative patients, multiplex ligation-dependent probe amplification of the SCN1A gene was performed in all cases; however, direct sequencing of the Protocadherin-19 (PCDH19) gene was analyzed in girls only.

Results: Fourteen (70.0%) DS patients were found to carry pathogenic SCN1A mutations, with 6 novel mutations. In SCN1A-negative patients; 1 of the 4 girl patients (25.0%) had a novel PCDH19 mutation, while none of the 6 patients had a large deletion or duplication in the SCN1A gene.

Conclusion: The SCN1A gene is the most common causative mutation in Thai children with DS phenotype. This study emphasizes the benefit of Sanger sequencing of the SCN1A gene in resource-limited countries to aid in making appropriate therapeutic decisions.

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Published

2021-09-08

How to Cite

1.
Viravan S, Meesamarnpong C, Thongnoppakhun W, Chanvanichtrakool M. Genetic Analysis of Children with Dravet Syndrome in a Resourcelimited Setting. J Health Sci Med Res [Internet]. 2021 Sep. 8 [cited 2022 Jun. 26];40(3):301-8. Available from: https://he01.tci-thaijo.org/index.php/jhsmr/article/view/255390

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