Dual E-Cigarette Users Show Nicotine Addiction Risk Alleles and Nuclear Abnormalities in Oral Epithelial Cells

Area of Science:

• Genetics and Genomics
• Addiction Research
• Toxicology

Background:

• Investigating genetic risk variants for nicotine addiction in genes like CHRNA5, HTR2A, DRD4, and CYP2A6.
• Assessing genotoxic and cytotoxic damage in oral mucosal cells of dual users (e-cigarette and combustible cigarette users).

Purpose of the Study:

• To identify genetic risk variants associated with nicotine addiction in dual users.
• To evaluate genotoxic and cytotoxic damage in the oral cells of dual users.

Main Methods:

• Genotyping of genetic variants in CHRNA5, HTR2A, DRD4, and CYP2A6.
• Inclusion of dual e-cigarette users (ECIG, n=70), combustible cigarette smokers (CCU, n=24), and non-smokers (NS, n=110).
• Micronucleus analysis on oral mucosal cells to detect cellular abnormalities.

Main Results:

• Dual users exhibited higher nicotine addiction (FTND scores) and salivary cotinine levels compared to combustible cigarette smokers.
• Carriers of specific alleles in CHRNA5, DRD4, and CYP2A6 were associated with increased nicotine addiction traits.
• Oral mucosal cells in dual users and smokers showed higher levels of micronuclei and abnormalities than non-smokers.

Conclusions:

• Dual e-cigarette use is linked to higher nicotine addiction and specific genetic risk variants.
• Genotoxic risks associated with dual e-cigarette use are comparable to those of combustible cigarette smoking.
• Findings highlight the genetic predisposition and cellular damage associated with dual nicotine product use.