Studies Find Genetic Factors in Smoking-Related Behaviors

WEDNESDAY, April 28 (HealthDay News) -- Genetic variants appear to play a role in several aspects of smoking behavior, according to three articles published online April 25 in Nature Genetics.

For all three articles, researchers performed genome-wide association studies for measures of smoking behavior related to smoking initiation, dependence and cessation. In one study, the researchers identified three loci that were associated with number of cigarettes smoked daily, with the strongest association found for a synonymous 15q25 single-nucleotide polymorphism (SNP) in the nicotinic receptor gene CHRNA3. Other SNPs were found to be associated with smoking initiation and cessation.

Two other studies focused attention on the genes encoding nicotine-metabolizing enzymes, CYP2A6 and CYP2B6, and the nicotinic acetylcholine receptor subunits CHRNB3 and CHRNA6, as well as CHRNA5, CHRNA3, and CHRNB4.

"Our findings suggests that separate genetic loci contribute modestly to phenotypic variability in each aspect of smoking behavior, which, in turn, may have implications for the way in which smoking cessation therapies and tobacco control efforts are designed and targeted," conclude the authors of the first study.

Several authors of one of the studies disclosed financial relationships with GlaxoSmithKline.

Abstract - Study 1
Full Text - Study 1 (subscription or payment may be required)
Abstract - Study 2
Full Text - Study 2 (subscription or payment may be required)
Abstract - Study 3
Full Text - Study 3 (subscription or payment may be required)