Furthermore, the TPH2(-/-) mouse may serve as a useful model in the search for new medications that have therapeutic targets for depression that are outside of the 5HT neuronal system.
The results of our analysis indicated no significant differences in the frequencies of the single alleles and genotypes of two polymorphisms in TPH2 gene between LOD patients and normal controls.
Common polymorphisms involved in the tryptophan hydroxylase 1 (TPH1) and 2 (TPH2), serotonin transporter, monoamine oxidase A (MAOA) and brain-derived neurotrophic factor (BDNF) were investigated in a naturalistic inpatient study of the German research network on depression.
We tested these mice along with C57BL/6 mice (Tph2C/C), congenic C57BL/6 mice homozygous for the Tph21473G-allele (Tph2G/G), and heterozygous Tph2-deficient mice (Tph2C/-) for anxiety- and depression-like behavior, and evaluated brain serotonin metabolism and 5-HT1AR signaling by high-performance liquid chromatography and quantitative autoradiography, respectively.
We hypothesize that functional polymorphisms (TPH2: rs7305115, 5-HTTLPR and rs25531) within both genes contribute to the risk of depressive disorders after childhood abuse in adult life.