They lead to severe neuropathological scenarios, collectively referred to as FOXG1 syndrome, for which no cure is so far available (Brimble et al., 2023; https://www.ncbi.nlm.nih.gov/clinvar/?term=Foxg1[gene]; Florian et al., 2011; Mitter et al., 2018; Papandreou et al., 2016; https://gene.sfari.org/database/human-gene/Foxg1#variants-tab; Vegas et al., 2018). The gene discussed is FOXG1; the disease is Down syndrome.