title: Bi-allelic and tri-allelic 5-HTTLPR polymorphisms and triptan non-response in cluster headache.
abstract: BACKGROUND
  Triptans are only effective in terminating cluster headache (CH) attacks in 70-80% of patients. Pharmacogenetic aspects of the serotonin metabolism, specifically variation in the 5-HTTLPR may be involved.
  
  
  METHODS
  Genetic association study in a well-defined cohort of 148 CH patients with information on drug response to triptans. CH was diagnosed according to the criteria of the International Headache Society. Genotypes of the 43-bp insdel (rs4795541) and A > G (rs25531) polymorphisms in the 5-HTTLPR promoter region were detected by restriction fragment length polymorphism analysis. We used logistic regression analysis to investigate the association between bi-allelic and tri-allelic genotypes and triptan non-response with genotype models.
  
  
  RESULTS
  Mean age at study entry among patients was 44.6 ± 10.5 years, 77.7% were men. The genotype distribution both for the bi-allelic and the tri-allelic polymorphism was in Hardy-Weinberg equilibrium. We did not find an association of the bi-allelic polymorphism with triptan non-response. While the effect estimates for the S variant of the tri-allelic polymorphisms suggested increased odds of triptan non-response in CH patients (multivariable-adjusted odds ratio [95% confidence interval]: L*L* genotype-reference; L*S* genotype-1.33 [0.53-3.32]; S*S* genotype-1.46 [0.54-3.98]), the results were not statistically significant.
  
  
  CONCLUSIONS
  Data from our study do not indicate a role of bi-allelic and tri-allelic genotypes of the 5-HTTLPR polymorphism in triptan non-response in CH.
authors.affiliation: Department of Neurology, University Hospital Essen, Hufelandstrasse 55, 45122 Essen, Germany. markus.schuerks@uni-due.de.
authors.forename: Markus
authors.initials: M
authors.lastname: Schürks
authors.forename: Antje
authors.initials: A
authors.lastname: Frahnow
authors.forename: Hans-Christoph
authors.initials: HC
authors.lastname: Diener
authors.forename: Tobias
authors.initials: T
authors.lastname: Kurth
authors.forename: Dieter
authors.initials: D
authors.lastname: Rosskopf
authors.forename: Hans-Jörgen
authors.initials: HJ
authors.lastname: Grabe
mesh_terms: D000328:Adult; D000483:Alleles; D003027:Cluster Headache / Q000188:drug therapy* / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D010597:Pharmacogenetics; D011110:Polymorphism, Genetic; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D014363:Tryptamines / Q000494:pharmacology*
chemical_list: C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D014363:Tryptamines