Furthermore, the correlation between regional Apo D expression pattern and sensitivity to neural pathology associated with these disorders suggests that Apo D is a marker for brain structures prone to neuropathology, such as the frontal cortex, entorhinal cortex, and hippocampus in AD, pre-frontal cortex in schizophrenia, and temporal cortex in bipolar disorder [17,19,20]. This evidence concerns the gene APOD and bipolar disorder.