Gene variation predicts response to hepatitis C treatments: study

WASHINGTON, Aug. 16 (Xinhua) -- A genetic variation that may predict response to hepatitis C treatments has been identified, U.S. researchers said on Sunday.

"This discovery enables us to give patients valuable information that will help them and their doctors decide what is best for them," said David Goldstein, a geneticist at Duke University and senior author on the study.

Hepatitis C affects an estimated 170 million people worldwide and is the leading cause of cirrhosis in the North America.

Treatment typically involves 48 weeks of interferon plus the antiviral drug ribavirin. Some patients develop such taxing side effects that they stop treatment.

Physicians have long observed that African-Americans are less likely to respond to treatments than Caucasians, while East Asian patients seem to respond the best. But no one has known why.

And now, according to Goldstein and his colleagues, a single letter change - a C instead of a T - in a tiny segment of DNA near the so-called IL28B gene is to blame.

The researchers found it by studying 1,671 people who participated in a clinical trial that compared the two most widely used therapies among patients with the most common form of the disease in the U.S. and Europe.

In their study, which was published on the website of the journal Nature, they found that hepatitis C patients who had the genetic variation were significantly more likely to respond to treatment than those who did not have it.