The study, published in the July 11, 2008 issue of PLoS Genetics, highlights the importance of public health efforts to reduce the number of youth who begin smoking.
These common gene variations, called single nucleotide polymorphisms (SNPs), are changes in a single unit of DNA. Scientists call SNPs that are linked and inherited together a haplotype. The researchers found that one haplotype for the nicotine receptor put European American smokers at greater risk of heavy nicotine dependence as adults, but only if they began daily smoking before the age of 17. A second haplotype actually reduced the risk of adult heavy nicotine dependence for people who began smoking in their youth.
The researchers studied 2,827 long-term European American smokers, recruited in Utah and Wisconsin, and to the National Heart, Lung, and Blood Institute’s Lung Health Study. They assessed the level of nicotine dependence for all smokers, and recorded the age they began daily smoking, the number of years they smoked, and the average number of cigarettes smoked per day. DNA samples were taken from all smokers, and the researchers recorded the occurrence of common SNPs, grouped into four haplotypes, which had been identified earlier in a subset of participants.
They found that people who began smoking before the age of 17 and possessed two copies of the high-risk haplotype had from a 1.6-fold to almost 5-fold increase in risk of heavy smoking as an adult. For people who began smoking at age 17 or older, presence of the high-risk haplotype did not significantly influence their risk of later addiction. The high-risk haplotype is common in the three study populations, and European American populations in general, ranging in frequency from 38 percent to 41 percent.
Although the authors caution that different haplotype frequencies would likely be observed in different ethnic populations, Robert Weiss, Ph.D., professor of human genetics at the University of Utah and lead author of the study explains, “We know that people who begin smoking at a young age are more likely to face severe nicotine dependence later in life. This finding suggests that genetic influences expressed during adolescence contribute to the risk of lifetime addiction severity produced from the early onset of tobacco use.”
According to Dr. Nora Volkow, director of the National Institute on Drug Abuse (NIDA), “In recent years we’ve seen an explosion in the understanding of how small genetic variations can impact all aspects of health, including addiction. As we learn more about how both genes and environment play a role in smoking, we will be able to better tailor both prevention and cessation programs to individuals.” The study was funded in part by NIDA and the National Heart, Lung, and Blood Institute (NHLBI), parts of the National Institutes of Health (NIH).
The NIDA-funded 2007 Monitoring the Future Study showed that 7.1% of 8th graders, 14.0% of 10th graders, and 21.6% of 12th graders had used cigarettes at least once in the month prior to being surveyed. Although cigarette use has declined slightly in youth in recent years, just over 3 million young people between the ages of 12 and 17, or 13 percent of those in the United States, still smoke cigarettes.
Chris Nelson | Newswise Science News
Transforming plant cells from generalists to specialists
07.12.2016 | Duke University
What happens in the cell nucleus after fertilization
06.12.2016 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
07.12.2016 | Earth Sciences
07.12.2016 | Earth Sciences
07.12.2016 | Materials Sciences