(HealthDay News) — For a subset of patients with interstitial cystitis/bladder pain syndrome (IC/BPS), pain perception may be influenced by the presence of a nonsynonymous single nucleotide polymorphism (SNP) in the SCN9A voltage-gated sodium channel, according to a study published online Oct. 25 in Urology.
Noting that SCN9A has previously been associated with other chronic pain syndromes, Jay E. Reeder, PhD, from the State University of New York Upstate Medical University in Syracuse, and colleagues sampled germline DNA from archived bladder biopsy specimens from 57 patients with IC/BPS and from hysterectomy specimens from 31 controls to examine the association between IC/BPS and an SNP in SCN9A. Samples were genotyped for rs6746030 after polymerase chain reaction (PCR) amplification.
PCR products were obtained from 26 controls and 53 IC/BPS specimens. The researchers found that 11.5 percent of the controls were genotype AG and the rest were GG. For patients with IC/BPS, 39.6% had AA or AG genotype (P=0.036). The frequency of the A allele was significantly higher for patients than controls (P=0.009).
“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,” the authors write.