title: Obsessive-compulsive disorder and the promoter region polymorphism (5-HTTLPR) in the serotonin transporter gene (SLC6A4): a negative association study in the Afrikaner population.
abstract: A polymorphism (5-HTTLPR) in the promoter region of the serotonin transporter gene (SLC6A4) has been reported to have functional significance and to be associated with obsessive-compulsive disorder (OCD). However, other studies have generated confounding results. A study was undertaken to re-evaluate this association in subjects drawn from the relatively genetically homogeneous Afrikaner population of South Africa. Fifty-four OCD patients of Afrikaner descent and 82 ethnically matched control individuals were phenotyped and genotyped. No significant association was found between the distribution of the 5-HTTLPR genotypes at the SLC6A4 locus and OCD. A similar result (p = 0.108) was generated when a meta-analysis of the 5-HTTLPR polymorphism, combining the current study with a previously reported Caucasian group, was performed; the meta-study comprised 129 OCD patients and 479 control individuals. However, both studies lacked power. Therefore, evidence that variation in SLC6A4 plays a significant role in the development of OCD in the population groups studied is inconclusive. Future association studies in Caucasian populations may extend the power of such meta-analyses and assist in delineating the role of SLC6A4 in OCD.
authors.forename: Craig J.
authors.initials: CJ
authors.lastname: Kinnear
authors.forename: Dana J. H.
authors.initials: DJ
authors.lastname: Niehaus
authors.forename: Johanna C.
authors.initials: JC
authors.lastname: Moolman-Smook
authors.forename: Pieter L.
authors.initials: PL
authors.lastname: du Toit
authors.forename: Jeanine
authors.initials: J
authors.lastname: van Kradenberg
authors.forename: Jakobus B.
authors.initials: JB
authors.lastname: Weyers
authors.forename: Annemarie
authors.initials: A
authors.lastname: Potgieter
authors.forename: Vanessa
authors.initials: V
authors.lastname: Marais
authors.forename: Robin A.
authors.initials: RA
authors.lastname: Emsley
authors.forename: James A.
authors.initials: JA
authors.lastname: Knowles
authors.forename: Valerie A.
authors.initials: VA
authors.lastname: Corfield
authors.forename: Paul A.
authors.initials: PA
authors.lastname: Brink
authors.forename: Dan J.
authors.initials: DJ
authors.lastname: Stein