Evaluation of genotoxic effect of different smoking habits by detecting micronucleus frequency in university students, A case control study

Background and objective: Cigarettes, shisha, and e-cigarettes are significant etiologic factors of oral cancers. Buccal mucosa is the first tissue that faces the pollutants and might reflect unhealthy processes in the body. Micronuclei are chromosomal fragments generated in interphasic cells. The present study was undertaken to investigate the association of cigarette, shisha, and e-cigarette use and micronucleus induction in the buccal mucosa. Methods: The present study was carried out on 120 healthy volunteers (56 males and 64 females) aged 18–30 years old and divided into four groups: e-cigarette consumers, cigarette smokers, shisha smokers, and non-smokers. After filling out the questionnaire, participants were asked to rinse their mouths with water, and then oral mucosa samples were taken, processed, and stained for micronucleus detection. Results: The frequency of micronucleus (mean ±SD) was 34.3±6.5 vs 16.76±4.27 (P <0.001), 37.1±8.31 vs 16.76±4.27 (P <0.001), 39.1±3.25 vs 16.76±4.27 (P <0.001) in cigarette vs control, shisha vs control, and e-cigarette vs control, respectively. Among the studied tobacco-related habits, and in respect to genotoxicity, e-cigarette revealed highest significant impact (P <0.001). In respect to the gender, no significant (P >0.05) differences were observed between male and female students who use tobacco related habits. Conclusion: The rate of exfoliated buccal epithelial cells with micronuclei in the buccal mucosa of e-cigarette, shisha, and cigarette users was significantly higher compared with the non-smokers group, which might lead to undesired clinical consequences. However, further studies concerning the association of genetic aberrations on the nucleotide level and tobacco-related habits are recommended. Keywords: Cigarette, E-cigarette, Genotoxicity, Micronucleus, Micronucleus assay, Shisha.