A critical appraisal of human genotyping for pain therapy

Despite intensive research, genetics-based personalized pain therapy has yet to emerge. Monogenetic heredity seems to be restricted to very rare and extreme phenotypes, whereas common phenotypes are very complex and multigenetic. Many common variants, of which only a fraction have been identified so far, produce only minor effects that are sometimes partly cancelled out. For most clinical settings and analgesic drug effects, common genetic variants cannot yet be used to provide a relevant prediction of individual pain and analgesic responses. However, genetics has some potential practical uses: CYP2D6, MC1R and potentially PTGS2 could provide guidance on the right choice of analgesics. After more than a decade of identifying genetic associations, the current challenge is to intensify compilation of this information for precisely defined clinical settings for which improved pain treatment is possible.