Blunted expression of PIK3R4/VPS15 (phosphoinositide‐3‐kinase regulatory subunit 4) is associated with neurodevelopmental impairment and cortical atrophy, matching the phenotype of patients bearing loss‐of‐function mutations in this gene (Gstrein et al, 2018). The gene discussed is PIK3R4; the disease is Cerebral cortical atrophy.