For example, as there is an inverse correlation between the DNA methylation of 5-HTT-linked polymorphic region and the left-amygdala volume (i.e., its DNA methylation reduces left-amygdala volume) [162], antipsychotic drug use is associated with less methylation of the 5-HTT (SLC6A4) promoter region both in postmortem brains and the saliva of patients with SCZ and BD [133]. The gene discussed is SLC6A4; the disease is Behcet disease.