美国新墨西哥州洛斯阿拉莫斯国家实验室的卢德米尔·亚历山大夫和同事,比较了2500名吸烟者和1000名非吸烟者的肿瘤DNA,发现平均每抽50根烟,每个肺细胞便会产生1个DNA突变。而每天抽20根烟的吸烟者连续抽一年,每个肺细胞、喉部细胞、咽部细胞、膀胱细胞和肾脏细胞分别会产生150个、97个、39个、18个和6个DNA突变。这是研究人员首次量化了分子损伤对DNA造成的影响。理论上,每个DNA突变都可能触发一连串基因损害,导致细胞癌变。然而,人们 Dr. Ludmil Alexander and colleagues at the Los Alamos National Laboratory in New Mexico, USA, compared the tumor DNA of 2,500 smokers and 1,000 non-smokers and found that on average every 50 cigarettes smoked each lung cell Produce a DNA mutation. Smokers smoked 20 cigarettes per day for a continuous year and produced 150, 97, 39, 18 and 6 DNAs per lung, throat, pharyngeal, bladder and kidney cells, respectively mutation. This is the first time researchers have quantified the effects of molecular damage on DNA. In theory, every DNA mutation could trigger a chain of genetic damage that leads to canceration of the cell. However, people