Anti-smoking advocates, when they push for bans on lighting up in public places, often point to studies linking exposure to secondhand smoke to diseases such as emphysema and cancer. Now they may have a new type of research to cite: evidence that secondhand smoke can alter a person’s genes
Time reports that a team of scientists at Weill Cornell Medical College led by Dr. Ronald Crystal studied the genetic activity of 121 volunteers. The volunteers were tested for exposure to cigarette smoke and divided into three groups: smokers, non-smokers and a middle group including occasional smokers and people whose only exposure to tobacco smoke was secondhand.
The researchers tested 25,000 genes to see which were activated — either turned on or off — by cigarette smoke. They found 372 genes that were active among the smokers but not in the nonsmokers. The middle group shared 11 percent of the same active genes as the group of smokers. The results, Time reported, suggest that nonsmokers exposed to secondhand smoke encounter genetic changes similar to smokers, changes that represent the first molecular steps toward lung disease.
“What is interesting to me is how sensitive the lung cells are to any cigarette smoke,” Crystal told Time. “It doesn’t matter if you are walking into a cocktail party where other people are smoking or if you smoke one cigarette a week. No matter what level of exposure you have, your lung cells know it and they are responding.”
