• Posted August 13, 2024

Smoking, Vaping Tied to Similar Unhealthy Changes in DNA

New research suggests that switching from smoking to vaping won't prevent some dangerous changes to a person's genome.

A new study conducted in young adults shows similar cancer-linked gene changes in both vapers and smokers.

“These findings have significant implications for public health and tobacco regulation that aim to keep vaping products away from young people, who are a particularly vulnerable population,” said study lead author Stella Tommasi. She's an associate professor of research population and public health sciences at the University of Southern California (USC), Los Angeles.

At issue is a process called DNA "methylation," essentially an on/off switch for genes that tells DNA if it should operate.

The new study looked at the genetics of 30 young adults averaging 23.5 years of age. Some were exclusive e-cigarette users, vaping at least three times per week for at least six months; some were exclusive smokers, smoking at least three times per week for at least a year; and some neither vaped nor smoked.

Tommasi's group used a high-tech gene sequencing technique to look at the genomes of cells taken from each participant in cheek swabs.

They found 831 "differentially methylated regions" (DMRs) in the genomes of vapers and 2,863 in smokers. DMRs are genetic areas that may be more or less methylated (switched on/off) in one person versus another.

Overall, there was a 46% overlap between the smokers and the vapers in terms of DMR groups, the researchers said.

"These methylated regions were on gene sites known to regulate important biological signaling pathways that drive disease development," according to a USC news release.

Most importantly, both smokers and vapers showed a DMR tied to a key region within HIC1, a tumor-suppressing gene. Changes in HIC1 have long been linked to lung cancer, suggesting the same processes may be happening to young adults who vape.

“Our findings indicate that the changes in DNA methylation observed in vapers may contribute to the development of disease, including cancer,” Tommasi said. “Electronic cigarettes are not as safe as some people claim that they are, even if the level of most toxicants and carcinogens present in e-liquid and vapor is generally much lower than that found in cigarette smoke."

The HIC1 finding could boost research efforts, she added.

“This is an exciting discovery because the methylation of this gene has never before been identified in vapers,” she noted.

The findings were published recently in the American Journal of Respiratory Cell and Molecular Biology.

More information

Find out more about vaping's harms to the lungs at the American Lung Association.

SOURCE: University of Southern California, news release, Aug. 12, 2024