Aoki et al., 2002 found significant interaction between the SNP and sex for analgesic requirement. Mutlu et al., 2004 report that the CC genotype is overrepresented in patients with temporomandibular dysfunction.
Negative studies: This polymorphism was not associated with fibromyalgia case status in Gursoy et al., 2001, Bondy et al., 1999, Tander et al., 2008 or Matsuda et al., 2010. Klepstad et al., 2011 found no significant associations of any 5HTR2A SNPs with opioid dose for cancer pain in cancer pain patients.