We investigated whether single nucleotide polymorphisms (SNPs) associated with neuroplasticity and activity of monoamine neurotransmitters, such as the brain-derived neurotrophic factor (BDNF, rs6265), the serotonin transporter (SLC6A4, rs25531), the tryptophan hydroxylase 1 (TPH1, rs1800532), the 5-hydroxytryptamine receptor 2A (HTR2A, rs6311, rs6313, rs7997012), and the catechol-O-methyltransferase (COMT, rs4680) genes, are associated with efficacy of transcranial direct current stimulation (tDCS) in major depression.
There was an increased risk of having MDD in homozygous female carriers of the TPH1 A-allele (odds ratio: 4.35) and homozygous carriers of the MAOA VNTR low activity allele 3R (odds ratio: 3.37).
Our aim was to assess the association of TPH1A218C polymorphism (rs1800532) with mood disorders, including major depressive disorder and bipolar disorder, and alcohol dependence by using meta-analysis.
The homozygous recessive genotype of the TPHA218C polymorphism has a significant effect on risk for bipolar disorder but not major depressive disorder.
The result suggests that 218A/C variants of TPH1cannot play a major role as predictor of treatment response as well as intolerance in Japanese patients with major depression.
Results suggest that the A218C polymorphism of the TPH gene does not play a major role in pathogenesis in MDD and does not serve as a modulator of antidepressant activity.
In this study, we examined whether polymorphism of the TPH1 gene is related to the etiology of major depression, anxiety and comorbid depression and anxiety.