Because up to 85% of all asymmetric synapses (i.e. synapses formed by glutamatergic terminals) in the cortex are formed almost exclusively on dendritic spines [59], and this amount is similar to the magnitude of reduction in vGluT1-immunoreactive profiles observed in this study, one interpretation of our finding is that the majority of the glutamatergic terminals that target pyramidal neurons in layer 3 of the PFC are functionally disturbed in schizophrenia and, among these terminals, approximately 20% are lost. The gene discussed is SLC17A7; the disease is schizophrenia.