Unexpected Sensory Variation Exclusive to African Americans – ScienceDaily

Menthol provides a minty, refreshing or soothing sensation and plays a particularly troubling role in cigarette smoking habits in the United States. According to the FDA, nearly 20 million people in the United States smoke menthol cigarettes, which are particularly popular among African-American smokers and teenage smokers. In the United States, 86% of African American smokers use menthol cigarettes, compared to less than 30% of smokers of European descent. In addition, menthol cigarettes may be more difficult to stop than other cigarettes.

Although the study did not focus initially on this study, the researchers also revealed clues as to how menthol could reduce the irritation and hardness of the cigarette.

"This study highlights the molecular mechanisms of how menthol interacts with the body," said Andrew Griffith, MD, Ph.D., Scientific Director and Acting Deputy Director of the National Institute of NIH on NIH deafness and other communication disorders (NIID). "These findings can help inform public health strategies aimed at reducing rates of harmful smoking among groups particularly vulnerable to the use of menthol cigarettes."

The research team, headed by Dennis Drayna, Ph.D., head of the section on Genetics of Communication Disorders at NIDCD, conducted detailed genetic badyzes on 1,300 adults. In the initial badyzes, researchers at the University of Texas Southwestern Medical Center in Dallas (UT Southwestern) used data from a group of multiethnic smokers from the Dallas Heart Study population and a group of smokers. African Americans from Dallas. Biobank. In collaboration with researchers from the Schroeder Institute® for Tobacco Research, Washington, DC, the scientists also confirmed their findings in a group of African-American smokers listed in Washington, D.C., Tobacco QuitlineTM.

The researchers reported that 5 to 8% of participants in the African-American study had the gene variant. None of the participants of European, Asian or Native American origin had the variant.

The identification of the genetic variant oriented the researchers in an unexpected direction, leading them to provide the first characterization of this natural variant of MRGPRX4 in humans. The gene codes for a sensor, or receptor, that would be involved in detecting and responding to environmental irritants in the lungs and airways.

"We were expecting genes related to taste receptors because menthol is an aromatic additive," said Drayna. "Instead, we discovered a different type of signaling molecule that seems to be involved in menthol preference."

Chapel Hill, researchers at the University of North Carolina (UNC), then collaborated with the research team to look more closely at the effect of the Africa-specific variant on MRGPRX4 receptor function. . They discovered that the variant modified a specific type of cellular signaling and that menthol modified it more. Additional studies have confirmed that this sensor is found in the airways, suggesting that menthol is likely to affect the way we perceive respiratory tract irritation.

"Although this variant of the gene can not explain all the increased use of menthol cigarettes by African Americans, our results indicate that this variant is a potentially important factor. Advertising practices in the sector have been at the heart of understanding from the use of menthol to the present.Our results indicate that genetic factors specific to Africa must also be taken into account, "Drayna said.

The FDA has solicited public comment and scientific information on the use of menthol in tobacco products. The agency has announced its intention to propose a ban on menthol-flavored cigarettes and cigars, largely because of the high consumption of menthol cigarettes among young people and young adults. More than half of smokers aged 12 to 17 smoke menthol cigarettes. According to the FDA, this prevalence reaches 7 out of 10 among young African-Americans who smoke.