Can't quit smoking? Blame your genes

April 3, 2008

I've always thought that some people had a more

" addictive " personality, myself included. Interesting that the

study sort of implies that, although they dealt specifically with

smoking. I suspect, had they looked for genes which make some people more

likely than others to say, gamble, get hooked on drugs, be an alcoholic -

whatever, they would have found a correlation. Not that's it's an excuse

- I've stayed away from gambling, for example, precisely because I

realize how I am with many things. That sometimes, there is a

genetic propensity to be the way you are. Interesting also, that some

people are more genetically pre-disposed to get cancer. Probably a lot of

other things as well, but they just haven't figured it out......But, it's

kind of nice to know you're not just weak, or easily swayed.

Lynn

Can't quit smoking? Blame your genes

New studies show ‘double whammy' link to addiction and

cancerWASHINGTON - Scientists say they have

pinpointed a genetic link that makes people more likely to get hooked on

tobacco, causing them to smoke more cigarettes, making it harder to quit,

and leading more often to deadly lung cancer.

The discovery by three separate teams of scientists makes the strongest

case so far for the biological underpinnings of the addiction of smoking

and sheds light on how genetics and cigarettes join forces to cause

cancer, experts said. The findings also lay the groundwork for more

tailored quit-smoking treatments.

" This is kind of a double whammy gene,'' said Christopher Amos, a

professor of epidemiology at the M.D. Anderson Cancer Center in Houston

and author of one of the studies. " It also makes you more likely to

be dependent on smoking and less likely to quit smoking.''

Greater cancer risk

A smoker who inherits this genetic variation from both parents has an

80 percent greater chance of lung cancer than a smoker without the

variants, the researchers reported. And that same smoker on average

lights up two extra cigarettes a day and has a much harder time quitting

than smokers who don't have these genetic differences.

The three studies, funded by governments in the U.S. and Europe, are

being published Thursday in the journals Nature and

NatureGenetics.

The scientists surveyed genetic markers in more than 35,000 people in

Europe, Canada and the United States, zeroing in on the same set of

genetic differences. They aren't quite sure if what they found is a set

of variations in one gene or in three closely connected genes. But they

said the result is the same: These genetic quirks increase the risk of

addiction and lung cancer.

The studies' authors disagreed on whether the set of variants directly

increased the risk of lung cancer or did so indirectly by causing more

smoking that led to the cancer.

The genetic variations, which encode nicotine receptors on cells, could

eventually help explain some of the mysteries of chain smoking, nicotine

addiction and lung cancer that can't be chalked up to environmental

factors, brain biology and statistics, experts said. These oddities

include why there are 100-year-old smokers who don't get cancer and

people who light up an occasional cigarette and don't get

hooked.

In the last 40 years, the rate of adult Americans smoking has been cut

from 42 percent in 1965 to less than 21 percent now.

The new studies point to surprising areas of the genes not associated

with pleasure and addiction rewards. That may help explain why people

have trouble quitting, said Dr. Nora Volkow, director of the National

Institute of Drug Abuse in Bethesda, Md., which funded one of the

studies. Eventual testing for the genetic variants could lead to custom

treatments for quitting smoking.

" This is really telling us that the vulnerability to smoking and how

much you smoke is clearly biologically based,'' said psychiatry professor

Dr. Laura Bierut, of Washington University in St. Louis, and a genetics

and smoking expert who did not take part in the studies. She praised the

research as " very intriguing.''

The studies mostly looked at smokers and ex-smokers although two of the

studies also looked at several hundred nonsmokers. The research only

involved white people of European descent. People of Asian and African

descent will be studied soon and may yield quite different results,

scientists said. Smoking-related diseases worldwide kill about one in 10

adults, according to the World Health Organization.

The studies show on average the consequences of the set of variations in

the alphabet of genetic code that people inherit from each parent:

Smokers who get the set of variants from only one parent see a risk

of lung cancer that is about one-third higher than people without any

variants. They also smoke about one more cigarette a day on average than

other smokers. This group makes up about 45 percent of the population

studied.

Smokers who inherit the variants from both parents have almost a one

in four chance of developing lung cancer. Their risk is between 70 and 80

percent higher than the cancer risk of other smokers without the genetic

variants. They smoke on average of two extra cigarettes a day, and have a

45 percent higher risk of peripheral artery disease. This group accounts

for about one in nine people of European descent.

Smokers who don't have the variants are still more than 10 times more

likely to get lung cancer than nonsmokers. Smokers without the variant

overall have about a 14 percent risk of getting lung cancer. By

comparison, the risk of lung cancer for people who have never smoked is

less than 1 percent, said another study author, Paul Brennan of the

International Agency for Research onCancer in Lyon, France.

Brennan and Amos, working on different teams, linked the genetic

variation itself when triggered by smoking directly to lung cancer.

Brennan said the nicotine receptors that the variants acton also can

stimulate tumor growth.

Join the discussion

Ever tried to quit smoking? Did you succeed?

Brennan's study also found that lung cancer risk for nonsmokers with the

variants was higher than for those without the variants. However, his

small sample size of nonsmokers requires further study. Amos' study

didn't find increased lung cancer risk for people with the set of

variants who have never smoked.

But Kari Stefansson, lead author of the largest of the three studies and

chief executive of deCode Genetics of Iceland, said the increased lung

cancer risk was indirect, and that the variant caused more addiction and

more smoking. It was the extra cigarettes from increased daily smoking

and the inability to quit that contributed to the higher cancer risk,

Stefansson said.

" It's very likely that in the end there's going to be a test and

this is going to be folded into a panel of tests for the risk of

cancers,'' said Stefansson, whose company already does prostate cancer

genetic tests. The tests will lead to better treatments, but probably not

prevention of smoking, he said.

Stefansson and others emphasize that people without the variants should

not take that genetic finding as a green light to smoke.There are other

smoking-related diseases and they would still be a thigh risk of lung

cancer.

For Stefansson, the research hits home. His father, a smoker,died of lung

cancer. And Stefansson, who doesn't smoke, frequently lectures his

23-year-old daughter " who smokes like a chimney.'' She acts like she

is immortal and smoking can't kill her, Stefansson said. But his own

research shows that her genes are probably stacked against her.

http://www.msnbc.msn.com/id/23919596/

April 3, 2008

Well, it is great you have something else to blame than yourself. Den 03/04/2008 kl. 17.44 skrev Lynn Ward:I've always thought that some people had a more "addictive" personality, myself included. Interesting that the study sort of implies that, although they dealt specifically with smoking. I suspect, had they looked for genes which make some people more likely than others to say, gamble, get hooked on drugs, be an alcoholic - whatever, they would have found a correlation. Not that's it's an excuse - I've stayed away from gambling, for example, precisely because I realize how I am with many things. That sometimes, there is a genetic propensity to be the way you are. Interesting also, that some people are more genetically pre-disposed to get cancer. Probably a lot of other things as well, but they just haven't figured it out......But, it's kind of nice to know you're not just weak, or easily swayed.LynnCan't quit smoking? Blame your genesNew studies show ‘double whammy' link to addiction and cancerWASHINGTON - Scientists say they have pinpointed a genetic link that makes people more likely to get hooked on tobacco, causing them to smoke more cigarettes, making it harder to quit, and leading more often to deadly lung cancer.The discovery by three separate teams of scientists makes the strongest case so far for the biological underpinnings of the addiction of smoking and sheds light on how genetics and cigarettes join forces to cause cancer, experts said. The findings also lay the groundwork for more tailored quit-smoking treatments."This is kind of a double whammy gene,'' said Christopher Amos, a professor of epidemiology at the M.D. Anderson Cancer Center in Houston and author of one of the studies. "It also makes you more likely to be dependent on smoking and less likely to quit smoking.''Greater cancer riskA smoker who inherits this genetic variation from both parents has an 80 percent greater chance of lung cancer than a smoker without the variants, the researchers reported. And that same smoker on average lights up two extra cigarettes a day and has a much harder time quitting than smokers who don't have these genetic differences.The three studies, funded by governments in the U.S. and Europe, are being published Thursday in the journals Nature and NatureGenetics.The scientists surveyed genetic markers in more than 35,000 people in Europe, Canada and the United States, zeroing in on the same set of genetic differences. They aren't quite sure if what they found is a set of variations in one gene or in three closely connected genes. But they said the result is the same: These genetic quirks increase the risk of addiction and lung cancer.The studies' authors disagreed on whether the set of variants directly increased the risk of lung cancer or did so indirectly by causing more smoking that led to the cancer.The genetic variations, which encode nicotine receptors on cells, could eventually help explain some of the mysteries of chain smoking, nicotine addiction and lung cancer that can't be chalked up to environmental factors, brain biology and statistics, experts said. These oddities include why there are 100-year-old smokers who don't get cancer and people who light up an occasional cigarette and don't get hooked.In the last 40 years, the rate of adult Americans smoking has been cut from 42 percent in 1965 to less than 21 percent now.The new studies point to surprising areas of the genes not associated with pleasure and addiction rewards. That may help explain why people have trouble quitting, said Dr. Nora Volkow, director of the National Institute of Drug Abuse in Bethesda, Md., which funded one of the studies. Eventual testing for the genetic variants could lead to custom treatments for quitting smoking."This is really telling us that the vulnerability to smoking and how much you smoke is clearly biologically based,'' said psychiatry professor Dr. Laura Bierut, of Washington University in St. Louis, and a genetics and smoking expert who did not take part in the studies. She praised the research as "very intriguing.''The studies mostly looked at smokers and ex-smokers although two of the studies also looked at several hundred nonsmokers. The research only involved white people of European descent. People of Asian and African descent will be studied soon and may yield quite different results, scientists said. Smoking-related diseases worldwide kill about one in 10 adults, according to the World Health Organization.The studies show on average the consequences of the set of variations in the alphabet of genetic code that people inherit from each parent:Smokers who get the set of variants from only one parent see a risk of lung cancer that is about one-third higher than people without any variants. They also smoke about one more cigarette a day on average than other smokers. This group makes up about 45 percent of the population studied.Smokers who inherit the variants from both parents have almost a one in four chance of developing lung cancer. Their risk is between 70 and 80 percent higher than the cancer risk of other smokers without the genetic variants. They smoke on average of two extra cigarettes a day, and have a 45 percent higher risk of peripheral artery disease. This group accounts for about one in nine people of European descent.Smokers who don't have the variants are still more than 10 times more likely to get lung cancer than nonsmokers. Smokers without the variant overall have about a 14 percent risk of getting lung cancer. By comparison, the risk of lung cancer for people who have never smoked is less than 1 percent, said another study author, Paul Brennan of the International Agency for Research onCancer in Lyon, France.Brennan and Amos, working on different teams, linked the genetic variation itself when triggered by smoking directly to lung cancer. Brennan said the nicotine receptors that the variants acton also can stimulate tumor growth. Join the discussion Ever tried to quit smoking? Did you succeed?Brennan's study also found that lung cancer risk for nonsmokers with the variants was higher than for those without the variants. However, his small sample size of nonsmokers requires further study. Amos' study didn't find increased lung cancer risk for people with the set of variants who have never smoked. But Kari Stefansson, lead author of the largest of the three studies and chief executive of deCode Genetics of Iceland, said the increased lung cancer risk was indirect, and that the variant caused more addiction and more smoking. It was the extra cigarettes from increased daily smoking and the inability to quit that contributed to the higher cancer risk, Stefansson said."It's very likely that in the end there's going to be a test and this is going to be folded into a panel of tests for the risk of cancers,'' said Stefansson, whose company already does prostate cancer genetic tests. The tests will lead to better treatments, but probably not prevention of smoking, he said.Stefansson and others emphasize that people without the variants should not take that genetic finding as a green light to smoke.There are other smoking-related diseases and they would still be a thigh risk of lung cancer.For Stefansson, the research hits home. His father, a smoker,died of lung cancer. And Stefansson, who doesn't smoke, frequently lectures his 23-year-old daughter "who smokes like a chimney.'' She acts like she is immortal and smoking can't kill her, Stefansson said. But his own research shows that her genes are probably stacked against her.http://www.msnbc.msn.com/id/23919596/

April 3, 2008

At 11:53 AM 4/3/2008, you wrote:

Ah, no - in the end, it is a person's responsibility - or fault. If they

know they have a problem with alcohol, they shouldn't drink it. Or,

anything like that. Once you realize you have issues with certain

things, you need to stay away from them. That is purely a choice thing. I

have never believed, and will never believe, that if one gets addicted to

something, it's not their fault. OK, it might not be totally their fault

in the sense that they might not have known it beforehand, but once

someone knows, it's up to them to quit. I don't buy the excuse,

" it's not their fault " when it comes to certain issues.

Enviroment and learning not withstanding. People grow up and they make

choices. It's as simple as that.

I know I should quite smoking for good, but haven't. That's my fault - no

one elses, regardless of what anyone says about genes. I did think it was

interesting, though, because I've noticed that certain people have

certain traits - as I said, for as long as I can remember, I've known I

have an addictive personality - I rarely do anything half-way. When I get

really interested in something, I, basically immerse myself in it.

But, like anything, I think people have certain potentials - in other

words, depending on what you do, what you eat, and so on, depends on

whether one lives up to whatever their potential is. For example, I

believe everyone is born with a potential to be a certain height. Whether

one achieves that, often has a lot to do with their environment and their

diet. Look at the Chinese and Japanese as examples - on the diet the used

to eat, most of them were very short. Once some of the western diet was

introduced, and they began eating some different things, as a

population(s), they are taller. some, quite a bit taller. There is a

noticeable and recordable difference in say, even just the last 40 years

or so. Pehaps even less.

I think, there are a lot of things that are like that, genetically, but

they just haven't found it out yet. One other real quick example of why I

believe this - I have a half-brother an sister from a previous marriage

on my father's side. He didn't really live with them, and was divorced

from his ex when the children were quite young. Yet, when I met my

half-brother, I was amazed - he was so like my dad in so many ways -

including the fact that he had a sort of disorganized organization. The

inside of his car, looked EXACTLY like the inside of my dad's car -

papers strewn here and there - they both used their cars as a sort of

office. This wasn't learned behavior. When my dad was married to his ex,

he was in the Navy, and his car was clean and neat. and, Skip (his son)

was very little. It seemed to me, and seems to be part of genetic history

he inherited. I'm much like my dad in certain ways, but not learned, or

even seen, until my personality was well developed -

Lynn

Well, it is great you have

something else to blame than yourself.

Den 03/04/2008 kl. 17.44 skrev Lynn Ward: