Related Experiment Video
Updated: Mar 16, 2026

Cigarette Smoke Exposure in Mice using a Whole-Body Inhalation System
Published on: October 22, 2020
Genetic Risk Can Be Decreased: Quitting Smoking Decreases and Delays Lung Cancer for Smokers With High and Low CHRNA5
Li-Shiun Chen1, Timothy Baker2, Rayjean J Hung3
1Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Siteman Cancer Center, Washington University, St. Louis, MO, USA.
Quitting smoking significantly reduces lung cancer risk and delays diagnosis by seven years, regardless of CHRNA5 genetic risk variants. These findings highlight the universal benefits of smoking cessation for all smokers.
Area of Science:
- Genetics
- Oncology
- Public Health
Background:
- Individuals with CHRNA5 high-risk variants face earlier lung cancer development.
- These variants are also linked to nicotine dependence and difficulty quitting smoking.
- The impact of smoking cessation on lung cancer risk for those with CHRNA5 risk variants remains unclear.
Purpose of the Study:
- To investigate if smoking cessation benefits lung cancer risk reduction are consistent across individuals with and without CHRNA5 risk variants.
- To determine the effect of smoking cessation on lung cancer incidence and age of diagnosis in relation to CHRNA5 genotype.
Main Methods:
- Meta-analysis of 15 studies from the International Lung Cancer Consortium.
- Examined 12,690 ever-smokers (6988 lung cancer cases, 5702 controls) with European ancestry.
- Focused on the CHRNA5 rs16969968 genotype and its association with smoking cessation and lung cancer risk.
Main Results:
- Smoking cessation was associated with a 52% reduction in lung cancer likelihood (OR=0.48).
- Among lung cancer patients, cessation delayed diagnosis by a median of 7 years (HR=0.68).
- The CHRNA5 rs16969968 risk genotype (AA) increased lung cancer risk and earlier diagnosis, but cessation benefits were similar for all genotypes.
Conclusions:
- Smoking cessation is highly beneficial for reducing lung cancer risk and delaying diagnosis, irrespective of CHRNA5 genetic risk status.
- Quitting smoking can halve the lung cancer risk and delay onset by 7 years for individuals with high-risk CHRNA5 genotypes.
- Findings support smoking cessation as a key preventive strategy for all smokers, potentially tailored by genetic risk.
More Related Videos
09:52Generation of High Quality Chromatin Immunoprecipitation DNA Template for High-throughput Sequencing ChIP-seq
Published on: April 19, 2013
09:50Impact Assessment of Repeated Exposure of Organotypic 3D Bronchial and Nasal Tissue Culture Models to Whole Cigarette Smoke
Published on: February 12, 2015
Related Concept Videos
Cancer Prevention
Some...
Pharmacogenomics: Identification of New Drug Targets
Stress Prevention and Stress Management Techniques IV
Pharmacogenetic Phenotypes: Alterations in Pharmacokinetics, Drug Targets and Biologic Milieu
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase
Relative Risk