In this model, tumour-inducing plasmids, knocking out three most commonly mutated genes of mesenchymal glioblastoma (Nf1, Trp53, Pten), were injected into the lateral ventricle of two-day old, anaesthetised mice pups, followed by electroporation of the brain; leading to the development of tumours that closely recapitulate the histopathological, molecular, and cellular features of human glioblastoma45,46. The gene discussed is PTEN; the disease is glioblastoma.