GAD1 and schizophrenia: Notably, although other IEGs such as c-Fos, c-jun, or EGR2 are also altered in schizophrenia, their expression levels are not correlated with GAD1 mRNA levels (Kimoto et al., 2014), which thus supports a specific role for EGR1 in GAD1 regulation and highlights its function as an important factor in the altered cortical GABA synthesis and cognitive functions observed in this neuropsychiatric disorder.