Life stress increases risk for developing post-traumatic stress disorder (PTSD), and more prominently so in short-allele carriers of the serotonin transporter linked polymorphic region (5-HTTLPR).
Further research is necessary to understand how early life stress interacts with 5-HTT genotypes to confer risk for suicidal behavior through psychological mechanisms.
Although, early life stress has been shown to alter the composition of the gut microbiota, it is not known whether a lower 5-HTT expression is also associated with an altered microbiome composition.
While SLC6A4 hypermethylation has typically been described to be independently associated with both early life stress and depressive disorders, only a few papers address whether methylation could mediate the interaction between stress and 5-HTTLPR in predicting psychopathological risk.
Caspi et al.'s 2003 report that 5-HTTLPR genotype moderates the influence of life stress on depression has been highly influential but remains contentious.
Although 5-HTTLPR has been shown to influence the risk of life stress-induced depression in the majority of studies, others have produced contradictory results, possibly due to weak effects and/or sample heterogeneity.
Simultaneously, the migrants were also happier if people in their country of origin had a higher frequency of 5-HTT long allele, a genotype known to be associated with resilience under life stresses.
The serotonin transporter (SERT) gene-linked polymorphic region (5-HTTLPR) has been implicated in moderating the link between life stress and depression.
This study aimed to test whether a specific serotonin transporter (5HTT) gene polymorphism interacting with life stress increased the risk of depression in patients with epilepsy.
Taken together, shorter leukocyte TL is significantly associated with the 5-HTTLPR S/S allelic variant, which may be implicated in psychological stress-related health problems.
To use data gathered over the course of a 30-year longitudinal study of a New Zealand birth cohort to test the hypothesis that the presence of short ('s') alleles of 5-HTTLPR are associated with an increased response to life stress.
Because the effects of the 5-HTTLPR polymorphism on amygdala reactivity are also conditional on self-reported life stress, differences in life stress exposure may account for this apparent discrepancy.
We hypothesized that peripheral blood mononuclear cell (PBMC) DNA methylation within an 800 bp cytosine-phosphate-guanosine (CpG) island that overlaps with the 5-HTT transcription initiation start site, a hypothesized model of the same genomic region in brain tissue, would mediate or moderate the effects of early life stress and a functional 5-HTT promoter polymorphism (rh5-HTTLPR) on two outcomes: PBMC 5-HTT expression and behavioral stress reactivity.
Recent reports of a moderating effect of a genetic polymorphism (5-HTTLPR) in the serotonin transporter protein gene on the likelihood that life stress will precipitate depression may help to understand the development of mood symptoms in medical interns.
Here we report an intrinsic immunobiological difference between individuals carrying two short (SS) versus long (LL) 5-HTTLPR alleles, that is observed in healthy subjects reporting low exposure to life stress.
Human observational studies have shown that, in interaction with life stress, the short or S-allele of the serotonin transporter gene-linked polymorphic region (5-HTTLPR) is associated with an enhanced risk for depression.
Visual perspective for positive memories was independently predicted by both harm avoidance and a gene by environment interaction between the 5-HTTLPR polymorphism and life stress exposure.
Lower 5-HTT BP(P) may represent a biological pathway through which early life stress predisposes to the development of subsequent psychiatric illness, including major depressive disorder.
These subjects had been genotyped for 5-HTT-LPR Short allele versus LL homozygote status, and completed the early life stress scale, and recording of startle responses and heart rate for conscious and nonconscious fear conditions.
Recent studies on life stress, depression, and polymorphisms in the promoter region of the serotonin transporter gene (5-HTTLPR) are characterized by powerful genetic techniques, but are also characterized by unconventional and inconsistent approaches to assessing life stress.
In the Mannheim Study of Risk Children, which followed a cohort of n = 384 from birth to adolescence, the association of 5-HTTLPR with harm avoidance and internalising problems was examined, including gender and early life stress as possible moderators.
Following a reductionistic path that leads from gene-behavior association studies to neuroimaging and epigenetic studies, we compare two models of 5-HTT-dependent modulation of brain activity and discuss the role of life stress experience in modifying 5-HTT function in the brain.