A common variation in a gene coding for a key brain enzyme increases susceptibility to pain, report researchers from the University of Michigan Medical Center and the National Institute on Alcoholism and Alcohol Abuse (NIAAA).
The enzyme, catechol O-methyltransferase (COMT), is vital to normal brain function, as it metabolizes the neurotransmitters norepinephrine and dopamine. The genetic variation changes a valine amino acid to a methionine, resulting in a three- to four-fold reduction in COMT's efficiency.