Et Cetera

Why are some people easily hooked on cigarettes while others drop the habit after a few puffs? The answer, according to a study of 4,775 sets of twins, which was reported in the New England Journal of Medicine, may lie in our chromosomes. Identical twins (who share the same genes) were somewhat more likely than fraternal twins (who don't) to exhibit the same behavior -- whether it is chain smoking, rarely smoking or quitting altogether. The study's results bolster the idea that heredity plays a role in why people start, stop or continue smoking.