CHICAGO (AP) — Researchers have identified common genetic traits that may explain how aspirin can help protect against colon cancer.

It’s too soon to recommend aspirin for colon cancer prevention and the needed genetic tests aren’t available outside of research. But they might be someday if future studies confirm the results.

Aspirin users were less likely than nonusers to get colon or rectal cancer if they had genetic traits found in about 90 percent of the participants. Cancer patients were less likely to have the beneficial traits, and less likely to be frequent aspirin users.

The results were published in Tuesday’s Journal of the American Medical Association.

Frequent aspirin use can cause intestinal bleeding so it’s not generally recommended for cancer prevention.