Dr. H. Westley Phillips was a co-first author on the recently published “Analysis of DNA from brain tissue on stereo-EEG electrodes reveals mosaic epilepsy-related variants” in Brain Communications. This study highlights a novel technique for performing genetic analysis on microscopic samples of epileptic brain tissue adherent to stereo-EEG depth electrodes following intracranial neuromonitoring. In this study, electrodes from 10 patients with drug-resistant epilepsy were collected enabling the discovery of brain-limited somatic variants from an otherwise discarded source of DNA. This innovative approach expands our ability to provide molecular genetic diagnoses to children with drug-resistant epilepsy beyond those that undergo open surgical resection while providing insights on the distribution of somatic variants across the epileptic brain.
Figure 1 Study workflow and confirmation of neuronal cells adhered to sEEG electrodes. (A) Study workflow including sEEG procedure, individual electrode collection, confirmation of neuronal cells on electrodes, parallel extraction of genomic DNA and whole-genome amplification (WGA) from individual electrodes, deep sequencing, variant analysis, and amplicon sequencing validation of variants in DNA derived from individual electrodes. Created in BioRender (https://BioRender.com/s54s494). (B) Epifluorescence image of sEEG electrode-derived tissue cultured cells 2 days post-surgical removal with antibody labelling of microtubule-associated protein 2 (MAP2, green), a neuron-specific cytoskeletal protein isoform for identifying neuronal cells and visualization of dendritic processes. Nuclear staining was performed with Hoechst 33342 (blue).
