A functional genetic variation of the serotonin (5-HT) transporter affects 5-HT1A receptor binding in humans JOURNAL OF NEUROSCIENCE David, S. P., Murthy, N. V., Rabiner, E. A., Munafo, M. R., Johnstone, E. C., Jacob, R., Walton, R. T., Grasby, P. M. 2005; 25 (10): 2586-2590


In humans, 5-HT1A receptors are implicated in anxiety and depressive disorders and their treatment. However, the physiological and genetic factors controlling 5-HT1A receptor expression are undetermined in health and disease. In this study, the influence of two genetic factors on 5-HT1A receptor expression in the living human brain was assessed using the 5-HT1A-selective positron emission tomography (PET) ligand [11C]WAY 100635. After the genotyping of 140 healthy volunteers to study population frequencies of known single nucleotide polymorphisms (SNPs) in the 5-HT1A receptor gene, the influence of the common SNP [(-1018) C>G] on 5-HT1A receptor expression was examined in a group of 35 healthy individuals scanned with [11C]WAY 100635. In the PET group, we also studied the influence of a common variable number tandem repeat polymorphism [short (S) and long (L) alleles] of the 5-HT transporter (5-HTT) gene on 5-HT1A receptor density. Whereas, the 5-HT1A receptor genotype did not show any significant effects on [11C]WAY 100635 binding, 5-HT1A receptor binding potential values were lower in all brain regions in subjects with 5-HTTLPR short (SS or SL) genotypes than those with long (LL) genotypes. Although the PET groups are necessarily a small sample size for a genetic association study, our results demonstrate for the first time that a functional polymorphism in the 5-HTT gene, but not the 5-HT1A receptor gene, affects 5-HT1A receptor availability in man. The results may offer a plausible physiological mechanism underlying the association between 5-HTTLPR genotype, behavioral traits, and mood states.

View details for DOI 10.1523/JNEUROSCI.3769-04.2005

View details for Web of Science ID 000227528600017

View details for PubMedID 15758168