Genetic Epilepsy

Gene: BSN

Comment when marking as ready: We are aware of additional mono allelic cases.

Created: 5 Jan 2023, 4:22 a.m. | Last Modified: 5 Jan 2023, 4:22 a.m.

Panel Version: 0.1829

Green List (high evidence)

Ye et al 2022, Neurogenetics https://jmg.bmj.com/content/early/2022/12/12/jmg-2022-108865
Identified 4 unrelated individuals with epilepsy and compound heterozygous BSN variants via trio WES (combination of null and missense). Homozygous knockout mouse models showed abnormal CNS transmission and seizure activity. None of the identified variants were present in population databases as homozygotes. One individual had ID and microcephaly but all other individuals with biallelic variants had normal development.

In addition, heterozygous variants were identified in unrelated affected individuals - 2 apparently co-segregating missense variants and 2 de novo null variants. These variants were either absent in population databases or rare. The authors note that affected individuals with heterozygous variants had milder disease - either requiring no therapy or monotherapy only. Heterozygous knockout mice had no phenotype and there were not enough affected individuals in the families to truly determine co-segregation. In addition, carrier parents of individuals with biallelic variants did not appear to be affected.

Association between biallelic variants and epilepsy stronger than for monoallelic.
Sources: Literature

Created: 5 Jan 2023, 3:55 a.m. | Last Modified: 5 Jan 2023, 4:44 a.m.

Panel Version: 0.1829

Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal

Phenotypes
Epilepsy MONDO:0005027