title: Polymorphism in the SCN9A voltage-gated sodium channel gene associated with interstitial cystitis/bladder pain syndrome.
abstract: OBJECTIVE
  To determine whether an association exists between interstitial cystitis/bladder pain syndrome (IC/BPS) and a nonsynonymous single nucleotide polymorphism in the SCN9A voltage-gated sodium channel gene previously associated with other chronic pain syndromes.
  
  
  METHODS
  Germline deoxyribonucleic acid was sampled from archived bladder biopsy specimens from patients with a documented diagnosis of IC/BPS. Deoxyribonucleic acid from hysterectomy specimens was obtained as a control population. The genotype of single nucleotide polymorphism rs6746030 was determined by deoxyribonucleic acid sequencing after polymerase chain reaction amplification. Contingency analysis of genotypes was performed using Pearson's chi-square test and Fisher's exact test.
  
  
  RESULTS
  Polymerase chain reaction product was obtained from 26 of 31 control specimens and from 53 of 57 IC/BPS biopsy specimens. Of the 26 control subjects, 3 (11.5%) were genotype AG and 23 were GG. In contrast, AA or AG genotypes were present in 21 of 53 (39.6%) patients with IC/BPS, a statistically significant difference compared with the controls (Pearson's chi-square, P=.036). Similarly, the A allele was at a greater frequency in the IC/BPS group using Fisher's exact test (P=.009).
  
  
  CONCLUSIONS
  These data strongly suggest that pain perception in at least a subset of patients with IC/BPS is influenced by this polymorphism in the SCN9A voltage-gated sodium channel.
authors.affiliation: Department of Urology, State University of New York Upstate Medical University, Syracuse, New York 13210, USA. reederj@upstate.edu
authors.forename: Jay E
authors.initials: JE
authors.lastname: Reeder
authors.forename: Timothy K
authors.initials: TK
authors.lastname: Byler
authors.forename: David C
authors.initials: DC
authors.lastname: Foster
authors.forename: Steve K
authors.initials: SK
authors.lastname: Landas
authors.forename: Henry
authors.initials: H
authors.lastname: Okafor
authors.forename: Gillian
authors.initials: G
authors.lastname: Stearns
authors.forename: Ronald W
authors.initials: RW
authors.lastname: Wood
authors.forename: Yachao
authors.initials: Y
authors.lastname: Zhang
authors.forename: Robert D
authors.initials: RD
authors.lastname: Mayer
mesh_terms: D000483:Alleles; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D018856:Cystitis, Interstitial / Q000235:genetics*; D005838:Genotype; D006801:Humans; D062556:NAV1.7 Voltage-Gated Sodium Channel / Q000235:genetics*; D058748:Pain Perception; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide; D012189:Retrospective Studies; D017422:Sequence Analysis, DNA
chemical_list: D062556:NAV1.7 Voltage-Gated Sodium Channel