Homozygous microdeletion in the FAAH-OUT pseudogene of the fatty acid amide hydrolase chromosomal region that is expressed in the brain and dorsal root ganglia was identified as the cause of congenital analgesia in a single individual (as of 2019). The individual experienced lifelong insensitivity to pain and was oblivious to cuts and burns, did not experience pain during childbirth, did not experience pain from degeneration of a hip that required hip replacement surgery, and did not require analgesics for postoperative pain. Furthermore, the individual exhibited expedited wound healing and reduced scarring, could not sense heat from chili peppers, did not experience depression, fear, and anxiety and lacked a normal fear response to erratic and aggressive behaviour. However, the individual also experienced slight memory impairment (was prone to losing the trail of thought while speaking, and experienced some forgetfulness), and could not experience thrill ("adrenaline rush").