Broken Genes, Broken Lives

Cancer touches every one of our lives in one way or another, seeming to show little care or concern for whom it attacks. There does not seem to be much we can do about preventing it, aside from eating more carefully and avoiding smoking. Perhaps because of the visceral nature of the disease that so clearly arises inside our bodies, unlike an infection transmitted by sex or perhaps an insect bite, cancer is commonly regarded as a genetic problem.

We’re told it is often hereditary, and this is a source of particular worry when common experience reveals that a couple of relatives in the extended family have had cancer. But since it is so common and so diverse, in most cases coincidence is a more likely explanation than inheritance. In fact, relative to the other major maladies of our time, cardiovascular disease, diabetes, asthma, and depression, cancer is the least attributable to a common set of genetic factors. Yet it certainly involves defective DNA. It is natural to ask, then, why would evolution tolerate our genes causing so much suffering?