2q24.3 Deletion

Kashima et al. “Efficacy of Dravet Syndrome Treatments in a Subset of Individuals
with 2q24.3 Deletion: A-5 Patient Case Series”. “Journal of Child Neurology” 2025, v. 0(0).

Dravet syndrome is characterized by recurrent, prolonged seizures and neurodevelopmental concerns. Approximately 80% of patients diagnosed with Dravet syndrome (DS) have genetic variants in a voltage-gated sodium channel (VGSC) gene called SCN1A. In 2022, an international DS expert consensus panel established a treatment algorithm including first- through fourth-line recommendations of anti-seizure medications. Kashima et al. performed a retrospective chart review describing five pediatric patients with 2q24.3 microdeletions involving SCN1A or other VGSC genes like SCN3A, SCN2A, SCN9A, and SCN7A. Each patient had a 2q24.3 microdeletion identified via chromosomal microarray. All patients presented with a history of seizures and global developmental delay. Other symptoms include G-tube dependence (4/5), scoliosis (2/5), autism spectrum disorder (1/5), and movement disorder (1/5). Four of the five patients had seizure onset before 4 months of age, which reflects prior reports of 2q24.3 deletion patients and is an onset earlier than expected of DS. The authors described utilizing the recommended DS treatments on the patients with 2q24.3 deletions. Among the DS treatments tried by 4 or 5 of the patients, cannabidiol had a universal efficacious response whereas valproic acid and clobazam demonstrated efficacy in at least half the patients tried. Overall, the authors suggest that seizures seen in 2q24.3 microdeletions may be secondary to the deletion of the VGSC genes and thus, affected individuals may benefit from similar anti-seizure medications prescribed to DS.

Chromosome Disorder Outreach Inc. medical geneticist and medical advisor Dr. Iosif Lurie M.D. Ph.D examines newly published research studies to locate the most important and relevant for our members. Synopses of these articles are then posted to our website’s research pages. Review and formatting by Nicole Talaba, MS CGC. For more information on any article please contact info@chromodisorder.org