Obsessive–compulsive disorder and the promoter region polymorphism (5-HTTLPR) in the serotonin transporter gene (SLC6A4): a negative association study in the Afrikaner population

• Published in: The international journal of neuropsychopharmacology 2000-12, Vol.3 (4), p.327-331, Article S1461145700002054
• Main Authors: Kinnear, Craig J., Niehaus, Dana J. H., Moolman-Smook, Johanna C., du Toit, Pieter L., van Kradenberg, Jeanine, Weyers, Jakobus B., Potgieter, Annemarie, Marais, Vanessa, Emsley, Robin A., Knowles, James A., Corfield, Valerie A., Brink, Paul A., Stein, Dan J.
• Format: Article
• Language: English
• Subjects: Brief Report
• ISSN: 1461-1457; 1469-5111
• DOI: 10.1017/S1461145700002054

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.