Detecting somatic variants in purified brain DNA obtained from surgically implanted depth electrodes in epilepsy.

Objective: Somatic variants causing epilepsy are challenging to detect, as they are only present in a subset of brain cells (e.g., mosaic), resulting in low variant allele frequencies.

Brain mosaicism of hedgehog signalling and other cilia genes in hypothalamic hamartoma.

Hypothalamic hamartoma (HH) is a rare benign developmental brain lesion commonly associated with a well characterized epilepsy phenotype. Most individuals with HH are non-syndromic without additional developmental anomalies nor a family history of disease. Nonetheless, HH is a feature of Pallister-Hall (PHS) and Oro-Facial-Digital Type VI (OFD VI) syndromes, both characterized by additional developmental anomalies.