Finally, bisulfite-sequencing analysis revealed that quetiapine decreased the DNA methylation level of the promoter region of SLC6A4, where hypermethylation with bipolar disorder and hypomethylation with mood stabilizers have been reported.
Abnormal expression and genetic polymorphism of SLC6A3 and SLC6A4 genes may increase the risk of developing mental illness, such as schizophrenia, bipolar disorder, ADHD, and aggressive behavior in Alzheimer disease, etc.
However, we found that CpG sites of SLC6A4, which were hypermethylated in patients with bipolar disorder, were hypomethylated in the neuroblastoma cells treated with mood stabilizers.
The 5-HTTLPR polymorphism could be a useful contributor, among other clinical variables, to predict the risk for manic switches when a patient with bipolar disorder is treated with antidepressant drugs.
Relative to the comparison subjects, subjects with bipolar disorder without panic disorder, but not those with comorbid bipolar disorder and panic disorder, showed significantly higher frequencies of the COMT Met158 and the short 5-HTTLPR alleles and genotypes.