报告称吸烟或永久性损伤你的遗传物质

AS IT IS 2016-10-01 Report: Smoking May Permanently¹ Damage Genetic² Material 报告称吸烟或永久性损伤你的遗传物质

Here is another reason to not light up a cigarette.

Smoking can permanently damage your genetic material, according to a new study.

Researchers at the Hebrew SeniorLife Institute for Aging Research say smoking leaves a long-term “footprint” on a person’s DNA³ or deoxyribonucleic acid. The researchers have ties to Harvard Medical School in the American state of Massachusetts.

DNA is the genetic material of which all living things are formed. Health problems, like heart disease and cancer, are believed to be at least partly a result of damage to a person’s DNA.

The changes in the genes⁴ are a result of a natural process called “DNA methylation.” It changes how the DNA works or operates, and possibly affects the body’s natural defenses against disease.

Roby Joehanes is the first author of a report on the study. He said the researchers found ‘compelling evidence’ that smoking has a long-lasting influence on our ‘molecular machinery⁵.’

“The encouraging news is that once you stop smoking, the majority of DNA methylation signals return to never smoker⁶ levels after five years, which means your body is trying to heal itself of the harmful impacts of tobacco smoking," he said.

However, cigarette smoking can still have an influence on people’s health more than 30 years after they stopped smoking, he said.

The researchers studied blood samples from 16,000 people, smokers⁷ and non-smokers alike. They found that for most, DNA damage resulting from smoking slowly disappeared five years after people quit smoking.

But some of the damage appeared to be permanent.

Researchers said in the study, the smokers experienced changes to more than 7,000 genes. That is about one-third of known human genes.

DNA methylation is one of the ways genes are expressed, or show up, in the body. It affects which genes ‘turn on’ and that can lead to the development of smoking-related diseases, said Dr. Stephanie J. London. She works at the U. S. National Institutes of Health and was another author of the study.

“Equally important is our finding that even after someone stops smoking, we still see the effects of smoking on their DNA,” she said.

Smoking is the leading cause of preventable health disorders⁸. It kills an estimated 480,000 Americans every year, according to the Centers for Disease Control and Prevention.

Smoking is believed to cause more than 6 million deaths worldwide each year, mostly through cancer, heart disease and lung disease.

Campaigns to get people to give up smoking have seen some success in the United States. Smoking levels have dropped. Now only an estimated 15 percent of the adult population smokes.

The study was published in the American Heart Association journal, Circulation: Cardiovascular Genetics.

Words in This Story

compelling – adj. very interesting and able to hold your attention

methylation – n. the process in which certain chemicals called “methyl groups” are added to proteins, DNA and other molecules⁹

author – n. someone who is a writer

impacts – n. effects

quit – v. stop doing something

1 permanently   

adv.永恒地，永久地，固定不变地

参考例句：

• The accident left him permanently scarred.那次事故给他留下了永久的伤疤。
• The ship is now permanently moored on the Thames in London.该船现在永久地停泊在伦敦泰晤士河边。

2 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

3 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

4 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

5 machinery   

n.(总称)机械，机器；机构

参考例句：

• Has the machinery been put up ready for the broadcast?广播器材安装完毕了吗？
• Machinery ought to be well maintained all the time.机器应该随时注意维护。

6 smoker   

n.吸烟者，吸烟车厢，吸烟室

参考例句：

• His wife dislikes him to be a smoker.他妻子不喜欢他当烟民。
• He is a moderate smoker.他是一个有节制的烟民。

7 smokers   

吸烟者( smoker的名词复数 )

参考例句：

• Many smokers who are chemically addicted to nicotine cannot cut down easily. 许多有尼古丁瘾的抽烟人不容易把烟戒掉。
• Chain smokers don't care about the dangers of smoking. 烟鬼似乎不在乎吸烟带来的种种危害。

8 disorders   

n.混乱( disorder的名词复数 )；凌乱；骚乱；（身心、机能）失调

参考例句：

• Reports of anorexia and other eating disorders are on the increase. 据报告，厌食症和其他饮食方面的功能紊乱发生率正在不断增长。 来自《简明英汉词典》
• The announcement led to violent civil disorders. 这项宣布引起剧烈的骚乱。 来自《简明英汉词典》

9 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。