COMT and panic disorder: Also, genotype distribution of the adenosine 2A receptor (ADORA2A) 1976T>C (rs5751876, formerly 1083T>C, Tyr/Tyr) variant, a silent polymorphism in exon 2 of the ADORA2A gene, which has previously found to be associated with panic disorder and anxiety-related traits [124]–[128], did not differ across COMT Val158Met genotype groups.