PTEN and nervous system disorder: Mutations or deletions of phosphatase and tensin homolog (PTEN) and the heterodimeric complex of tuberous sclerosis proteins 1 and 2 (TSC1/hamartin, TSC2/tuberin) can dramatically upregulate mTOR signaling and contribute to a class of human neurological diseases characterized as “TORopathies” (Crino, 2009; Wong and Crino, 2012).