Serotonin Transporter: Difference between revisions

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The gene that encodes the SERTs is SLC6A4. The promoter region of SLC6A4 has two well-known polymorphisms aptly named “short” and “long” corresponding to the number of repeats in the  5-HTT-linked polymorphic region (HTTLPR). The short variation of this promoter leads to less transcription of the SERT gene SLC6A4. <ref>PMID:8929413</ref> Further, studies have found that the short allele of HTTLPR is associated with changes in the brain structure such as reduced grey matter in the perigeniculate region surrounding Cg25 and in the amygdala, areas important for emotional processing and mood regulation.<ref>DOI:10.1038/nn1944</ref> Massive genetic analysis of autistic patients reveals that the S allele is present significantly more in patients with [[Autism]] than without.<ref>PMID:16103890</ref> Since the presence of the short-HTTLPR promoter results in fewer SERTs being produced, and SERTs function by reuptaking and thus limiting serotonin-induced signal transduction, it is not unexpected that over 30% of autistic individuals, who more commonly have the short-HTTLPR allele, have elevated concentrations of serotonin.<ref>PMID:15749252</ref> These elevated concentrations of serotonin also explain why [[Pharmaceutical Drugs|pharmaceutical therapeutics]] like selective serotonin reuptake inhibitors (SSRIs), including the well-known Zoloft and Prozac (both benzodiazepines), have been shown to alleviate some symptoms of autism. The same is true for the well-known Obsessive-Compulsive disorder (OCD), patients of which suffer from intrusive mental tics resulting in repetitive rituals such as washing their hands obsessively often.<ref>PMID:17677845</ref> Although OCD is believed to be caused by aberrant functioning of glutamate responsive synapses, treatment with serotonin reuptake inhibitors helps treat symptoms of OCD possibly because serotonin modulates glutamate action, as validated by mouse models.(HYMAN)