Moreover, HepaCAM is strongly expressed in the white matter, implicated in leukodystrophy and regulates the activity of glioblastoma cells (Favre-Kontula et al., 2008; López-Hernández et al., 2011; Jeworutzki et al., 2012; De et al., 2023), whereas the overall structure of the brain appears not to be affected by the absence of BT-IgSF (Figs. 1B,D, 6A, Extended Data Figs. 2-1, 6-1). This evidence concerns the gene HEPACAM and leukodystrophy.