By Josh Grossberg

Researchers at the Keck School of Medicine of USC have been awarded a five-year, $1.8 million grant to study the links between genetics, tobacco addiction and withdrawal in African-Americans.

Adam Leventhal, assistant professor of preventive medicine and psychology and director of the USC Health, Emotion and Addiction Laboratory, will be the principal investigator of the study, which is being funded by the American Cancer Society.

“(African-Americans) have a lower rate of smoking,” Leventhal said. “And they smoke fewer cigarettes a day than whites, but they have a higher risk of cancer, which makes it critical to study the causes of nicotine addiction in African-Americans.”

Over the course of the study, 770 people will give a blood sample and have their genes analyzed. Then they will return to the lab after not smoking for 16 hours and will be tested to determine which nicotine withdrawal symptoms they are experiencing.

After only 16 hours of not smoking, nicotine withdrawal symptoms can include anxiety, sadness, irritability, hunger and concentration problems. These symptoms are important factors that can make people relapse to smoking after making an attempt to quit.

“We look at the change from when they’re normally smoking to when they have been without cigarettes for 16 hours,” Leventhal said. “That change tells us how severe the withdrawal is. The idea is that different genes will predict higher or lower levels of withdrawal.”

The answers could help determine why some people find it easier to quit than others.

“Some people get very severe withdrawal symptoms and others don’t,” Leventhal said. “Some people get really irritable when they quit. Others do not get irritable at all. If we can understand which genes cause these differences, we can develop new medications that target biological factors regulated by these genes.