The serotonin transporter (5-HTT) gene contains a variable number tandem repeat (VNTR) domain within intron 2 that is often associated with a number of neurological conditions, including affective disorders.
We applied meta-analysis techniques to case-control studies of two 5-HTT polymorphisms and two affective disorders (BP and UP), resulting in four meta-analyzes.
In our sample of 814 patients comprising 114 with schizophrenia, 416 with bipolar affective disorder and 284 with unipolar affective disorder, we studied interactions between the tryptophan hydroxylase (TPH), the serotonin transporter (5-HTTLPR), and the dopamine receptor (DRD4) genes in relation to five major psychiatric symptomatology scores.
As such, the 5-HTTLPR may represent a classic susceptibility factor for affective disorders by biasing the functional reactivity of the human amygdala in the context of stressful life experiences and/or deficient cortical regulatory input.
We investigated the serotonin transporter gene (5-HTTLPR) in the functioning of euthymic patients with mood disorders (n=285) and healthy controls (n=94).
Serotonin transporter promoter length polymorphism (5-HTTLPR) has been implicated in the pathogenesis of mood disorders and in the therapeutic response to serotonergic drugs.
A functional polymorphism within the promoter region of the 5-HTT gene, leading to different transcriptional efficiency, was repeatedly reported to influence the response to SSRIs in mood disorders while the response of patients with OCD seems unrelated.
Negative affect such as depression and anxiety has been reported to be associated with morbidity and mortality, and polymorphisms of the serotonin transporter (5HTT) gene may be associated with such affect disorders.
These results suggest that neuroticism mediates the association between 5HTT-LPR genotype and lifetime major depression, consistent with models of the aetiology of depression which suggest that anxiety-related personality traits represent a substantial risk factor for affective disorder.
In turn, corticolimbic circuit function predicts individual differences in an experimental index of temperamental anxiety and, thus, might reflect a predictive biological marker of increased risk for mood disorders associated with the 5-HTTLPR.
A functional polymorphism (a 44-base pair insertion (L)/deletion (S)) in the promoter of the gene encoding the serotonin transporter (5-HTTLPR), associated with mood disorders, has been inconsistently associated with suicidality.
Polymorphism at the serotonin transporter linked polymorphic region (5-HTTLPR) has been associated with neuroticism, increased risk for affective disorders and greater vulnerability to mood change following serotonin (5-HT) depletion.
Mood disorder subjects (N=191) and healthy volunteers (N=125), all Caucasian subjects of European origin, were genotyped for the triallelic 5-HTTLPR polymorphism (higher expressing allele: L(A); lower expressing alleles: L(G), S).
Therefore, SERT knockout mice can be used as a tool to study 5-HTTLPR-related variations in personality and may be the etiology of affective disorders.
The serotonin transporter gene promoter polymorphism (5-HTTLPR) has been repeatedly associated with antidepressant response in mood disorder patients, but findings are not consistent across studies.
We investigated the influence of 5-HTT-linked polymorphic region (5-HTTLPR) and 5-HTT 17 bp variable number of tandem repeat polymorphism (5-HTTVNTR) polymorphisms on concentrations of monoamine metabolites in cerebrospinal fluid (CSF) among treatment-resistant patients with mood disorders.
In the present study, we evaluated the impact of the BDNF Val66Met polymorphism on individual differences in personality traits in a sample of healthy volunteers in relation to other common gene variants thought to be involved in the pathophysiology of affective disorders, such as the serotonin transporter promoter polymorphism (5-HTTLPR) and a variable number of tandem repeat polymorphism of the dopamine transporter gene (DAT VNTR).
Several studies have implicated an insertion/deletion polymorphism in the promoter region of the serotonin transporter gene (SLC6A4; 5-HTT) in the development of mood disorders.
Such alterations suggest a broad role of the 5-HTT gene in brain function that may be associated with the genetic susceptibility for mood disorders such as depression.
Further investigations in larger samples are needed to clarify the usefulness of 5-HTTLPR and BDNF Val66Met genotyping in the optimization of non-pharmacological treatments in mood disorders.