title: A quantitative epigenetic approach for the assessment of cigarette consumption.
abstract: Smoking is the largest preventable cause of morbidity and mortality in the world. Despite the development of numerous preventive and treatment interventions, the rate of daily smoking in the United States is still approximately 22%. Effective psychosocial interventions and pharmacologic agents exist for the prevention and treatment of smoking. Unfortunately, both approaches are hindered by our inability to accurately quantify amount of cigarette consumption from the point of initial experimentation to the point of total dependency. Recently, we and others have demonstrated that smoking is associated with genome-wide changes in DNA methylation. However, whether this advance in basic science can be employed as a reliable assay that is useful for clinical diagnosis and treatment has not been shown. In this communication, we determine the sensitivity and specificity of five of the most consistently replicated CpG loci with respect to smoking status using data from a publically available dataset. We show that methylation status at a CpG locus in the aryl hydrocarbon receptor repressor, cg05575921, is both sensitive and specific for smoking status in adults with a receiver operated curve characteristic area under the curve of 0.99. Given recent demonstrations that methylation at this locus reflects both intensity of smoking and the degree of smoking cessation, we conclude that a methylation-based diagnostic at this locus could have a prominent role in understanding the impact of new products, such as e-cigarettes on initiation of cigarette smoking among adolescents, while improving the prevention and treatment of smoking, and smoking related disorders.
authors.affiliation: Department of Psychiatry, University of Iowa, Iowa City, IA USA ; Behavioral Diagnostics, Iowa City, IA USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Philibert
authors.affiliation: Department of Psychiatry, University of Iowa, Iowa City, IA USA.
authors.forename: Nancy
authors.initials: N
authors.lastname: Hollenbeck
authors.affiliation: Behavioral Diagnostics, Iowa City, IA USA.
authors.forename: Eleanor
authors.initials: E
authors.lastname: Andersen
authors.affiliation: Behavioral Diagnostics, Iowa City, IA USA.
authors.forename: Terry
authors.initials: T
authors.lastname: Osborn
authors.affiliation: Department of Psychology-Center for Health Intervention and Prevention, University of Connecticut, Storrs, CT USA.
authors.forename: Meg
authors.initials: M
authors.lastname: Gerrard
authors.affiliation: Department of Psychology-Center for Health Intervention and Prevention, University of Connecticut, Storrs, CT USA.
authors.forename: Frederick X
authors.initials: FX
authors.lastname: Gibbons
authors.affiliation: Department of Biostatistics, College of Public Health, University of Iowa, Iowa City, IA USA.
authors.forename: Kai
authors.initials: K
authors.lastname: Wang
keywords: DNA methylation; aryl hydrocarbon receptor repressor; cg05575921; diagnostics; e-cigarettes; epigenetics; smoking