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Impact Assessment of Repeated Exposure of Organotypic 3D Bronchial and Nasal Tissue Culture Models to Whole Cigarette Smoke
Published on: February 12, 2015
Sequence variants at CHRNB3-CHRNA6 and CYP2A6 affect smoking behavior
Thorgeir E Thorgeirsson1, Daniel F Gudbjartsson, Ida Surakka
1[1] deCODE Genetics, Reykjavik, Iceland. [2] Center for Biomolecular Science and Engineering, Jack Baskin School of Engineering, University of California, Santa Cruz, California, USA.
Nature Genetics
|April 27, 2010
Summary
This study identified new genetic regions linked to the number of cigarettes smoked daily. These findings advance our understanding of smoking behaviors and their genetic underpinnings.
Area of Science:
- Genetics
- Public Health
- Pharmacogenomics
Background:
- Smoking is a major global health risk factor.
- Genetic predispositions significantly influence smoking behaviors, including initiation and quantity consumed.
- Identifying genetic variants associated with smoking can inform prevention and cessation strategies.
Purpose of the Study:
- To conduct genome-wide association meta-analyses to identify genetic variants associated with the number of cigarettes smoked per day (CPD) and smoking initiation.
- To replicate and validate identified single nucleotide polymorphisms (SNPs) in independent cohorts.
- To explore the association of identified genetic loci with lung cancer risk.
Main Methods:
- Genome-wide association meta-analyses were performed on large cohorts (n > 31,000 for CPD, n > 46,000 for initiation).
- Replication analysis involved in silico testing of selected SNPs in additional cohorts (n = 45,691 and n = 9,040).
- Statistical significance was assessed using stringent thresholds (P < 5 x 10(-8)).
Main Results:
- Three genomic regions significantly associated with CPD were identified, including previously known variants at 15q25 (rs1051730) and novel loci at 19q13 (rs4105144) and 8p11 (rs6474412).
- Genes near the newly identified loci include those encoding nicotine-metabolizing enzymes (CYP2A6, CYP2B6) and nicotinic acetylcholine receptor subunits (CHRNB3, CHRNA6).
- Nominal associations were found between variants at 8p11 and 19q13 and lung cancer risk.
Conclusions:
- The study successfully identified novel genetic loci influencing the number of cigarettes smoked per day.
- The identified genes are biologically plausible candidates involved in nicotine metabolism and signaling.
- These genetic findings contribute to understanding the complex interplay between genetics, smoking behavior, and disease risk, including lung cancer.
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