Navigation Links
How genetics shape our addictions
Date:9/11/2012

This press release is available in French.

Have you ever wondered why some people find it so much easier to stop smoking than others? New research shows that vulnerability to smoking addiction is shaped by our genes. A study from the Montreal Neurological Institute and Hospital - The Neuro, McGill University shows that people with genetically fast nicotine metabolism have a significantly greater brain response to smoking cues than those with slow nicotine metabolism. Previous research shows that greater reactivity to smoking cues predicts decreased success at smoking cessation and that environmental cues promote increased nicotine intake in animals and humans. This new finding that nicotine metabolism rates affect the brain's response to smoking may lead the way for tailoring smoking cessation programs based on individual genetics.

Smoking cues, such as the sight of cigarettes or smokers, affect smoking behavior and are linked to relapse and cigarette use. Nicotine metabolism, by a liver enzyme, also influences smoking behavior. Variations in the gene that codes for this enzyme determine slow or fast rates of metabolism and therefore, the level of nicotine in the blood that reaches the brain. In the study smokers were screened for their nicotine metabolism rates and their enzyme genotype. Participants were aged 18 35 and smoked 5-25 cigarettes daily for a minimum of 2 years. People with the slowest and fastest metabolism had their brain response to visual smoking cues measured using functional MRI. Fast metabolizers had significantly greater response to visual cigarette cues than slow metabolizers in brain areas linked to memory, motivation and reward, namely the amygdala, hippocampus, striatum, insula, and cingulate cortex.

"The finding that nicotine metabolism rate has an impact on the brain's response to smoking cues supports our hypothesis that individuals with fast nicotine metabolism rates would have a greater brain response to smoking cues because of close coupling in everyday life between exposure to cigarettes and surges in blood nicotine concentration. In other words they learn to associate cigarette smoking with the nicotine surge," says clinician-scientist Dr. Alain Dagher, lead investigator at The Neuro. "In contrast, individuals with slow metabolism rates, who have relatively constant nicotine blood levels throughout the day, are less likely to develop conditioned responses to cues. For them, smoking is not associated with brief nicotine surges, so they are smoking for other reasons. Possibilities include maintenance of constant brain nicotine levels for cognitive enhancement (ie, improved attention, memory), or relief of stress or anxiety. "

Future research could focus on improving smoking cessation methods by tailoring treatments for different types of smokers. One possibility is to measure the rate of nicotine metabolism as part of the therapeutic decision-making process. For example, targeting cue-induced relapse risk may not help those with slow nicotine metabolism, who are more likely to benefit from long-acting cholinergic drugs such as the nicotine patch, consistent with previous clinical trials. Conversely the use of non-nicotine based therapies aimed at reducing craving may help fast metabolizers, as demonstrated for buproprion, an anti-depressant that has been used for smoking cessation.


'/>"/>
Contact: Anita Kar
anita.kar@mcgill.ca
514-398-3376
McGill University
Source:Eurekalert

Related medicine news :

1. Optogenetics project takes top NIDA Addiction Science Award
2. Brave New World of Genetics Requires Safeguards, Experts Say
3. Odds of quitting smoking affected by genetics
4. Stanford study shows opiates side effects rooted in patients genetics
5. American Society of Human Genetics to hold 2012 annual meeting, Nov. 6 to 10, in San Francisco
6. Marin Countys high breast cancer rate may be tied to genetics
7. Genetics Society of Americas Genetics journal highlights for September 2012
8. More Babies Today Have Irregular Head Shape: Expert
9. New technique predictably generates complex, wavy shapes
10. Shape Up, Safely, for Summer
11. Dads Early Engagement With Son May Shape Behavior Later
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/28/2017)... ... 2017 , ... Starting in May, patients at The Bay Clinic of ... diagnostic test. , Nerve-Express, originally designed for the Navy in the 1980s, measures the ... patient’s autonomic nervous system (ANS). The ANS controls all the critical unconscious functions ...
(Date:5/28/2017)... ... May 28, 2017 , ... Viewers likely know Rob Lowe from such ... also noted for his work on NBC’s The West Wing and Parks and Recreation. ... new series “Informed,” which puts the spotlight on important modern-day issues that face today’s ...
(Date:5/27/2017)... ... May 27, 2017 , ... From May 21-23, hearing healthcare professionals ... event was held at the Marriott Syracuse Downtown Hotel in Syracuse, New York. ... network of independent hearing healthcare providers to help them stay ahead in the industry. ...
(Date:5/26/2017)... ... May 26, 2017 , ... ... CEO 2017 on May 30th and 31st at The Four Seasons Hotel Boston. ... executives in the life sciences, offering exclusive access to key decision makers who ...
(Date:5/26/2017)... ... , ... A new analysis of community health data reveals that four out ... Midwest. With the average cost of healthcare rising and the U.S. senior population expected ... and affordability of where they live. An annual 2017 report looked at a variety ...
Breaking Medicine News(10 mins):
(Date:5/4/2017)... May 4, 2017  A recent study published ... Ultraviolet-C light as a means of disinfection ... to reduce bioburden on anesthesia workstations. In the ... high-touch, complex medical equipment surfaces contaminated with three ... "This study further validates the body of ...
(Date:5/4/2017)... SAN DIEGO , May 4, 2017 /PRNewswire/ ... Annual Clinical and Scientific Meeting— OBP Medical , a ... today announced the launch of a new extra-small size ... and ER-SPEC vaginal specula. Already available in ... extra-large sizes makes OBP Medical,s line of single-use lighted ...
(Date:5/4/2017)... 4, 2017  A new tight-tolerance microextrusion medical ... highly-engineered materials, is being launched by Natvar, a ... developed in recent years to service a wide ... applications. More expensive materials such as glass and ... due to their ability to consistently hold tolerances. ...
Breaking Medicine Technology: