SLC6A4 polymorphism, population genetics, and psychiatric traits.

5HTTLPR, which is the trivial name for a variable number of tandem repeats (VNTR) polymorphism mapped to the 5' region of the SLC6A4 (serotonin transporter protein) gene, is one of the most studied variants with respect to psychiatric traits. It is also widely studied in the context of intermediate phenotypes such as neuroimaging measures, and gene-by-environment interaction, the latter generally in the context of affective and anxiety phenotypes. In this article, the author discusses the importance of the variant in the context of a population genetics article published in Human Genetics sixteen years ago.