|(-;AGATGCTGGGGGGGCTGCAGGGGGGATGCTGGGGGTGCAGGGG)||complex; see details|
|(AGATGCTGGGGGGGCTGCAGGGGGGATGCTGGGGGTGCAGGGG;AGATGCTGGGGGGGCTGCAGGGGGGATGCTGGGGGTGCAGGGG)||complex; see details|
This SNP has been studied in many contexts, including the following:
- Anxiety related behaviours and disorders
- Response to anti-depressant drugs
- Seasonality and seasonal affective disorder
- Premature ejaculation
- Men with the LL genotype ejaculate about twice as quickly as men with SS or SL genotypes on average, based on a study of 89 Dutch men who suffer from the primary form of premature ejaculation. 
- Attention deficit disorder
- Bipolar mood disorder
- Obsessive compulsive disorder
- Irritable bowel syndrome
It is beyond the current scope to summarize all the associations seen for this SNP, as well as the lack of replication reported in some follow-on studies.
[PMID 20502016] Polymorphism C in the Serotonin Transporter Gene in Depression-Free Elderly Patients with Vascular Dementia
[PMID 17629953] Loudness dependence of auditory evoked potentials is not associated with polymorphisms or haplotypes in the serotonin transporter gene in a community-based sample of German healthy volunteers.
[PMID 18081710] Multivariate permutation analysis associates multiple polymorphisms with subphenotypes of major depression.
[PMID 19721846] Candidate genes involved in neural plasticity and the risk for attention-deficit hyperactivity disorder: a meta-analysis of 8 common variants.
[PMID 19940176] Functional variation of the dopamine D2 receptor gene is associated with emotional control as well as brain activity and connectivity during emotion processing in humans.
[PMID 23728717] Common functional polymorphisms in SLC6A4 and COMT genes are associated with circadian phenotypes in a South American sample