A international team of scientists has used data from genome-wide association studies to identify genetic variants associated with key smoking behaviors that have a significant impact on health.

CNCR researcher Danielle Posthuma was part of the statistical analysis subgroup of the largest genetic study of smoking to date, called the Tobacco and Genetics Consortium (TAG).
The TAG consortium is led by UNC-Chapel Hill genetics faculty members and UNC Lineberger members Helena Furberg, PhD and Patrick Sullivan, MD, collaborating with scientists from 16 large genetic studies world-wide, including the VU-NTR and -NESDA GAIN cohorts. They compared the DNA marker profiles between smokers and non-smokers to examine whether genetic variants affect whether people start to smoke. They also compared the DNA among smokers to see if genetic variants affected the number of cigarettes smoked per day, the age when people began to smoke and whether smokers were able to quit.

In a paper published this week in the journal Nature Genetics, the team reported that three genetic regions were associated with the number of cigarettes smoked per day, one region was associated with smoking initiation and one variant was associated with smoking cessation. The variants on chromosome 15 that were associated with heavy smoking lie within a region that contains nicotinic receptor genes, which other scientists have previously associated with nicotine dependence and lung cancer.

Genome-wide association studies (GWAS) search for genetic variants involved in a disease which may ultimately help prevent, diagnose, and treat the disease. Because smoking behavior is associated with many diseases, such as heart disease and cancer, the researchers were able to assemble more data to test the links between genetic variants and smoking than any one study could provide alone. The Tobacco and Genetics Consortium also collaborated with two other groups from Europe to confirm their findings; all three papers appear in Nature Genetics.

Statistical analyses for TAG were carried out on the Genetic Cluster Computer, which is supported by the Netherlands Scientific Organization and directed by CNCR researcher Posthuma.