This was based on the finding that regional protein levels of SV2A are highly correlated with in vivo specific binding of [11C]UCB-J31 and the main finding of our clinical study that [11C]UCB-J binding is significantly reduced in the frontal and anterior cingulate cortices of volunteers with schizophrenia who were receiving antipsychotic medication, as compared to controls. This evidence concerns the gene SV2A and schizophrenia.