Navigation Links
If your first cigarette gave you a buzz and you now smoke, a gene may be to blame
Date:8/8/2008

ANN ARBOR, Mich. Anyone who has ever tried smoking probably remembers that first cigarette vividly. For some, it brought a wave of nausea or a nasty coughing fit. For others, those first puffs also came with a rush of pleasure or "buzz."

Now, a new study links those first experiences with smoking, and the likelihood that a person is currently a smoker, to a particular genetic variation. The finding may help explain the path that leads from that first cigarette to lifelong smoking.

The new finding also adds to growing suspicion surrounding the role of a particular nicotine-receptor gene in smoking-related behaviors and in lung cancer. Other researchers have already linked variations in the same genetic region to smokers' level of dependence on nicotine, to the number of cigarettes smoked per day and to a far higher risk of lung cancer the ultimate outcome of a lifetime of smoking.

In a paper published online today in the journal Addiction, a multi-university collaborative team of researchers specializing in statistical genetics, gene analysis, and trait analysis reports an association between a variant in the CHRNA5 nicotine receptor gene, initial smoking experiences, and current smoking patterns.

The genetic and smoking data come from 435 volunteers. Those who never smoked had tried at least one cigarette but no more than 100 cigarettes in their lives, and never formed a smoking habit. The regular smokers had smoked at least five cigarettes a day for at least the past five years.

The regular smokers in the study were far more likely than the never-smokers to have the less common rs16969968 form of the CHRNA5 gene, in which just one base-pair in the gene sequence was different from the more common form. This kind of genetic variation is called a single nucleotide polymorphism or SNP.

Smokers were also eight times as likely to report that their first cigarettes gave them a pleasurable buzz.

"It appears that for people who have a certain genetic makeup, the initial physical reaction to smoking can play a significant role in determining what happens next," says senior author and project leader, Ovide Pomerleau, a professor of psychiatry at the University of Michigan Medical School and founder of the U-M Nicotine Research Laboratory.

"If cigarette smoking is sustained, nicotine addiction can occur in a few days to a few months," he adds. "The finding of a genetic association with pleasurable early smoking experiences may help explain how people get addicted and, of course, once addicted, many will keep smoking for the rest of their lives."

The researchers point out that the genetic variant explains only a portion of human smoking behavior, and that a more complete explanation of why people smoke and why they can't quit will require much more information about how genes interact with social influences and other environmental factors.

Pomerleau predicts that the ability to link behavioral patterns in smoking to individual genotypes will need extensive information concerning behavior, genes, and the environmental context as well as bioinformatic tools to bring it all together. "Understanding the genetics of complex disorders such as nicotine addiction will require much more research on key traits," he says.

The team notes that the CHRNA5 relationships appear to be strong and that practical applications from this research include new genetic tests for smoking risk and the development of medications that target smoking-risk genes.

Pomerleau states that the new paper builds on findings reported last year by fellow author Laura Bierut, in which a whole-genome study found that the same single nucleotide polymorphism, rs16969968, of the CHRNA5 gene was associated with smokers' level of nicotine dependence.

He also notes that, this year, three papers published independently of one another demonstrated that variations in the same gene, and related genes, greatly increase the risk of lung cancer.

Taking into account its links to increased liking of initial smoking, stronger likelihood of getting addicted to nicotine, and greater probability of developing lung cancer, this genetic variant may well constitute a "triple whammy" for smoking-related disease, he says.

A mechanism for explaining increased disease risk, proposed by one of the cancer genetics researchers, is the possibility that certain chemicals, for instance N-nitrosonornicotine in tobacco smoke, act on nicotine receptors in the lung to produce cancer-causing changes a process known as tumorigenesis.

The new findings linking first smoking experiences, smoking habits, and genetic variation build on previous research by Ovide Pomerleau and Cynthia Pomerleau, Ph.D., at U-M. In studies conducted over a 10-year span, they documented a link between nicotine-dependent smoking and positive first smoking experiences.


'/>"/>

Contact: Kara Gavin
kegavin@umich.edu
734-764-2220
University of Michigan Health System
Source:Eurekalert

Related biology news :

1. Which came first, the moth or the cactus?
2. First all-African GM crop is resistant to maize streak virus
3. Scientists retrace evolution with first atomic structure of an ancient protein
4. CU-Boulder team discovers first ancient manioc fields in Americas
5. First finding of a metabolite in 1 sex only
6. First orchid fossil puts showy blooms at some 80 million years old
7. First individual genome sequence published
8. U of M begins nations first clinical trial using T-reg cells from cord blood in leukemia treatment
9. UNH becomes first university in nation to use landfill gas as primary energy source
10. Scientists in first global study of poison gas in the atmosphere
11. Weight gain between first and second pregnancies associated with increased odds of male second child
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/19/2016)... , UAE, April 20, 2016 ... be implemented as a compact web-based "all-in-one" system solution ... the biometric fingerprint reader or the door interface with ... of modern access control systems. The minimal dimensions of ... ID readers into the building installations offer considerable freedom ...
(Date:4/15/2016)... 2016 Research and Markets has ... Market 2016-2020,"  report to their offering.  , ... ,The global gait biometrics market is expected to ... period 2016-2020. Gait analysis generates multiple ... used to compute factors that are not or ...
(Date:4/13/2016)... -- IMPOWER physicians supporting Medicaid patients in Central ... in telehealth thanks to a new partnership with higi. ... patients can routinely track key health measurements, such as ... when they opt in, share them with IMPOWER clinicians ... retail location at no cost. By leveraging this data, ...
Breaking Biology News(10 mins):
(Date:4/28/2016)... Hill, Conn. (PRWEB) , ... April 28, 2016 ... ... of financing and ongoing support for Connecticut's innovative, growing companies, today announced the ... digital health and financial technology (fintech) companies. , “VentureClash looks to ...
(Date:4/27/2016)... ... , ... Shimadzu Scientific Instruments (SSI) will be showcasing a ... and Expo. Shimadzu’s high-performance instruments enable laboratories to test cannabis products for potency, ... by booth 1021 to learn how Shimadzu’s instruments can help improve QA/QC testing, ...
(Date:4/27/2016)... ... April 27, 2016 , ... The Board of Directors of ... John Tilton as Chief Commercial Officer.  Mr. Tilton joined Biohaven from Alexion Pharmaceuticals, ... leaders responsible for the commercialization of multiple orphan drug indications. Mr. Tilton ...
(Date:4/27/2016)... ... ... Global Stem Cells Group and the University of Santiago Biotechnology ... development initiatives for potential stem cell protocol management for 2016 – 2020. , ... meeting to establish a working agenda and foster initiatives to promote stem cell research ...
Breaking Biology Technology: