title: Opposing alterations in anxiety and species-typical behaviours in serotonin transporter overexpressor and knockout mice.
abstract: Human gene association studies have produced conflicting findings regarding the relationship between the 5-HT transporter (5-HTT) and anxiety. In the present study genetically modified mice were utilised to examine the effects of changes in 5-HTT expression on anxiety. In addition, the influence of 5-HTT expression on two innate "species-typical" behaviours (burrowing and marble burying) and body weight was explored. Across a range of models, 5-HTT overexpressing mice displayed reduced anxiety-like behaviour whilst 5-HTT knockout mice showed increased anxiety-like behaviour, compared to wildtype controls. In tests of species-typical behaviour 5-HTT overexpressing mice showed some facilitation whilst 5-HTT knockout mice were impaired. Reciprocal effects were also seen on body weight, as 5-HTT overexpressors were lighter and 5-HTT knockouts were heavier than wildtype controls. These findings show that variation in 5-HTT gene expression produces robust changes in anxiety and species-typical behaviour. Furthermore, the data add further support to findings that variation of 5-HTT expression in the human population is linked to changes in anxiety-related personality traits.
authors.affiliation: Department of Experimental Psychology, South Parks Road, Oxford, OX1 3UD, United Kingdom.
authors.forename: Samantha J
authors.initials: SJ
authors.lastname: Line
authors.forename: Christopher
authors.initials: C
authors.lastname: Barkus
authors.forename: Clare
authors.initials: C
authors.lastname: Coyle
authors.forename: Katie A
authors.initials: KA
authors.lastname: Jennings
authors.forename: Robert M
authors.initials: RM
authors.lastname: Deacon
authors.forename: Klaus P
authors.initials: KP
authors.lastname: Lesch
authors.forename: Trevor
authors.initials: T
authors.lastname: Sharp
authors.forename: David M
authors.initials: DM
authors.lastname: Bannerman
mesh_terms: D000818:Animals; D001007:Anxiety / Q000235:genetics* / Q000378:metabolism; D001008:Anxiety Disorders / Q000235:genetics* / Q000378:metabolism; D001522:Behavior, Animal; D001835:Body Weight; D005260:Female; D006801:Humans; D008297:Male; D018782:Maze Learning; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009043:Motor Activity; D012701:Serotonin / Q000378:metabolism; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D050486:Serotonin Plasma Membrane Transport Proteins; D012701:Serotonin