University research suggests individuals with greater sensitivity to bitter tastes are less likely to develop a dependence on nicotine than those with a lower sensitivity to such tastes.

“If a person is a [sensitive] taster, then that person is less likely to become a smoker,” said lead investigator Ming Li, professor of psychiatry and neurobehavioral sciences. “In other words, [being a] taster is kind of protective and [being a] non-taster is kind of like a risk factor.”

Li explained that the research project consisted of two components, the first of which was published in the Journal of Medical Genetics and the second of which was published in the American Journal of Human Genetics. The first component of the research focused on genetic analysis of DNA samples taken from more than 2,200 human subjects over a period of nearly 10 years, Li said. The individuals taking part in the study were classified as tasters, non-tasters or intermediate, Li said. If a person was classified as a non-taster, he or she was more likely to become a smoker.

The second component of the research introduced a mathematically based methodology that provided a novel method of detecting gene-gene interaction for other human genetic researchers, Li said, and was used to analyze genetic data on two taste receptor genes, known as TAS2R16 and TAS2R38. The researchers found that these two genes interact with each other in the development of smoking dependence. This component of the research extended the finding of the first report, and together the research offers a “complete story,” Li said.

Jamie Mangold, a former research assistant in Li’s lab who was primarily involved in the first component of the study, commented that the development of the research between the two publications focused on the role of the taste receptor genes.

There was evidence in earlier research, Mangold said, indicating that people who are more sensitive to bitter substances are less likely to be smokers and drinkers. Mangold said she looked through the literature and thought that taste could be a major factor.

“With publication of the first paper, we kind of decided that the TAS2R16 gene was not a primary player … but after the second paper we realized that the TAS2R16 gene may also be important through its interaction with TAS2R38,” Mangold said.

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