Correlation between epilepsy and genotype: A large retrospective tuberous sclerosis complex cohort

Area of Science:

• Genetics
• Neurology
• Rare Diseases

Background:

• Tuberous sclerosis complex (TSC) is a genetic disorder affecting multiple organs.
• Epilepsy is a common and significant complication of TSC.
• Understanding genotype-phenotype correlations is crucial for managing TSC.

Purpose of the Study:

• To characterize the first large Chinese cohort of individuals with TSC.
• To investigate the relationship between TSC1/TSC2 gene variants and epilepsy in this population.
• To analyze how variant type and location influence epilepsy severity.

Main Methods:

• Next-generation sequencing of TSC1 and TSC2 genes in 297 individuals.
• Analysis of variant distribution and detection rates.
• Statistical comparison of epilepsy prevalence, type, and age of onset based on genotype.

Main Results:

• Epilepsy affected 83.5% of the cohort; TSC1/TSC2 variant detection rate was 89.6%.
• Individuals with TSC2 variants had significantly higher epilepsy rates, more spasms, and earlier onset compared to TSC1 or no mutation identified (NMI) groups.
• Variants in TSC2 functional domains were associated with increased epilepsy risk and earlier onset.

Conclusions:

• This study provides the first large-scale genotype-phenotype analysis of TSC in China.
• TSC2 variants are associated with more severe epileptic phenotypes.
• Targeting functional domains in TSC2 may be key for understanding and managing epilepsy in TSC.