The most recently discovered member of the D2 subfamily, the D4 receptor, is also attracting interest for similar reasons. Of particular note are findings from a postmortem study which showed a 6-fold increase in D4 receptor binding in he brains of people diagnosed with schizophrenia compared with controls. Clozapine has a 10-fold greater affinity for the D4 than the D2 receptor and this may be the basis of its antipsychotic action. Clozapine's lack of extra pyramida adverse effects may be related to the fact that only low levels of D4 receptors are found in the striatum.