5HTT

5HTT, also known as SERT or SLC6A4, is a protein that functions as a serotonin transporter. It is encoded by the SLC6A4 gene in humans. This transporter is primarily located on the presynaptic membranes of neurons in the central nervous system and also on platelets in the bloodstream. Its main role is to reuptake serotonin from the synaptic cleft back into the presynaptic neuron. This process is crucial for regulating the duration and intensity of serotonergic neurotransmission.

The activity of the 5HTT transporter is influenced by genetic variations, with common polymorphisms in the SLC6A4 gene, particularly in the promoter region, affecting transporter expression levels and function. These variations have been studied in relation to various neuropsychiatric conditions, including depression, anxiety disorders, and obsessive-compulsive disorder. Some research suggests that certain variants may be associated with an increased risk or altered response to these conditions, though findings are not always consistent across studies.

Beyond its role in neurotransmission, 5HTT also plays a part in serotonin homeostasis and has implications for drug interactions, as many antidepressant medications, such as selective serotonin reuptake inhibitors (SSRIs), target and inhibit the 5HTT transporter to increase serotonin levels in the synapse. The complex interplay between 5HTT genetics, function, and behavior continues to be an active area of research.