Progressive myoclonus epilepsy associated with SACS gene mutations

Area of Science:

• Genetics
• Neurodegenerative Diseases
• Epilepsy

Background:

• Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a rare neurodegenerative disorder.
• Pathogenic variants in the SACS gene are the known cause of ARSACS.
• Progressive myoclonus epilepsies (PMEs) are a group of rare, severe epilepsy syndromes.

Purpose of the Study:

• To investigate the genetic basis of unclassified progressive myoclonus epilepsies (PMEs).
• To identify novel genetic causes for PMEs.
• To characterize the clinical features of PME associated with SACS gene mutations.

Main Methods:

• Whole-exome sequencing was performed on a cohort of patients with unclassified PMEs.
• Genetic analysis identified mutations in the SACS gene in two patients.
• Clinical data from these patients were reviewed and analyzed.

Main Results:

• Two patients with unclassified PMEs were found to harbor mutations in the SACS gene.
• The identified SACS gene mutations were associated with specific PME clinical features.
• This finding expands the known phenotypic spectrum associated with SACS gene mutations.

Conclusions:

• The SACS gene should be considered in the genetic diagnosis of patients presenting with PMEs.
• Mutations in the SACS gene can manifest as PME, in addition to ARSACS.
• This research highlights the genetic heterogeneity of PMEs and the importance of comprehensive genetic screening.