An individual’s pain tolerance, or lack of, may be genetic, according to new research. The research, which will be presented at the American Academy of Neurology, suggests that genetics play an important role in determining why some people have a higher pain tolerance than others.

The study, which was released on April 20, shows that researchers may have found key genes linking higher pain tolerance in some people than in others.

Study author Dr. Tobore Onojjighofia, MPH, said in the official press release, “Our study is quite significant because it provides an objective way to understand pain and why different individuals have different pain tolerance levels.” Onojjighofia continues, “Identifying whether a person has these four genes could help doctors better understand a patient’s perception of pain.”

For the study, researchers evaluated 2,721 people with chronic pain for specific genes. The participants took prescription opioid pain medications. The genes that were studied include COMT, DRD2, DRD1 and OPRK1. The participants were asked to rate their level of pain on a scale of zero to 10. Those who listed their pain as zero were not included in the study. A score of one through three represented a low pain perception while four to six was moderate and seven through 10 indicated high pain perception.

Nine percent of study participants had a low pain perception, while 46 percent had moderate pain perception and 45 percent had high pain perception.

Researchers discovered that the DRD1 gene variant was 33 percent more common in the low pain group than in the high pain group. Those in the moderate pain group were more likely to have two variants: COMT, which was 25 percent more prevalent in the high pain group and OPRK, which was 19 percent more prevalent. The high pain group had a 25 percent higher chance of having DRD2 than those in the moderate group.