THREE DECADES after quitting
Smoking has a lasting effect on health, even after quitting, experts reveal
But scientists say the good news is that most of the damage is repaired within five years of neglect, which means it’s never too late to stop.
unhealthy habit leaves its permanent mark in the form of ‘DNA methylation’, a process by which cells control gene activity
The results, published in the journal Circulation: Cardiovascular Genetics .. suggest that might reveal the smoking history of an individual, that offers hope to develop better therapies
Dr. Stephanie London, the National Institute of Environmental Health Sciences of the USA, said: “These results are important because methylation, as one of the mechanisms regulation of gene expression, affects which genes are activated, which has implications for the development of diseases related to snuff.
Smoking has a huge impact, the extent of their genes
“Equally important is the finding, even after someone quits smoking, we still see the effects of smoking in their DNA.”
Smoking remains the leading preventable cause of death in the world, despite a decline in many countries as a result of campaigns and legislative measures.
Even decades after quitting, former smokers have a long-term risk of developing cancer, chronic obstructive pulmonary disease and stroke.
smoking life can leave a mark in their DNA, affecting their genes
the molecular mechanisms remain poorly understood, but previous studies linking DNA methylation sites for genes involved with coronary heart disease and lung disease suggests that it may play an important role.
Dr. London and colleagues pooled data from 16 previous studies that analyzed blood samples from a total of 16,000 people.
found smokers associated DNA methylation sites associated with more than 7,000 genes, about a third of all known human genes.
For people who had, most returned back to the levels observed in smokers never within five years.
Negative effects on genes may be a factor in heart and lung disease
however, some persisted even after 30 years of being free of nicotine.
Most statistically significant proportion were linked to genes associated with numerous diseases caused by smoking, including heart disease and certain cancers.
The discovery raises the possibility of developing biomarkers to assess the patient’s smoking history and potentially the development of new treatments directed toward these methylation sites.
lead author, Dr. Roby Joehanes, of Harvard Medical School in the US, said: “Our study has found compelling evidence of smoking have a lasting impact on our molecular machinery, an impact that can last more than 30 years
smoking is one of the major preventable causes of death around the world
“the good news is that once you stop smoking, most signals DNA methylation never to levels smoker after five years, which means your body is trying to heal itself from the harmful effects of snuff consumption. “
Dr London said the identification of DNA changes related to smoking can lead to diagnostic tests that can more accurately assess the smoking history of the patient
She said: “. You can use this data to estimate the prior smoking people. Nobody says that the smoke when they do not, but say they do not smoke when they do, so they could use these signals to find out.
“Almost no time this information is helpful. Especially with a condition related to snuff, if you have an excellent biomarker consumption of snuff, which can pinpoint the effects of other exposures in a more rigorous way. ”
Dr. Norman Edelman, senior scientific advisor to the American Lung Association, said the new study “raises some tantalizing questions” despite not being able to establish a cause and effect relationship between genetic changes related with smoking and health problems stemming
He said, “those who deal with smoking as a public health problem understanding anything we look at that seems to be affected by smoking.”.
This includes many types of cancer, bone diseases, lung disease, heart disease, and gastrointestinal problems.
Dr. Edelman added: “The message here is smoking has a huge impact, the extent of their genes
.” Most of it is reversible, but some is not. So if you smoke, you will alter their genetic makeup in a way that is not fully reversible. “