Tegeder et al. tested 15 SNPs in 168 Caucasion adults; five were significant.
Negative findings: Kim and Dionne, 2007 failed to find any significant association of 38 SNPs with thermal and cold pain sensitivity in 735 healthy volunteers or with clinical pain response after third molar extraction in 221 subjects. Klepstad et al., 2011 reported no association of three of the five Tegeder SNPs on opioid use in a large cohort of 2294 cancer patients. Wadley et al., 2012 found no independent association of SNPs or haplotypes with pain from HIV-associated sensory neuropathy in an African cohort. Also see Lazarev et al., 2008; Holliday et al., 2009.