PHTS patients with destabilizing PTEN mutations and proteasome hyperactivity are more susceptible to develop neurologic symptoms such as mental retardation and autism than mutation-positive patients with normal proteasome activity.
PTEN mutations have been more recently reported in children with macrocephaly and autism spectrum disorders or mental retardation, without other symptoms of PHTS.
The expression of mutant isocitrate dehydrogenase 1 (IDH1), α-thalassemia X-linked intellectual disability (ATRX), p53, phosphatase and tensin homolog (PTEN), and epidermal growth factor receptor (EGFR) was examined immunohistochemically; for 1p19q analysis we used fluorescence in situ hybridization (FISH).