1. Archive

Is it all in the genes?

(ran TP, CI editions)

It's not for us to resolve the question of who lives a long life and who doesn't. Sometimes, though, it seems that fate defies logic. We can all think of examples of people who died young when it seemed they would live long. A relative of mine died of stomach cancer after eating healthfully all her life. I know of a physically fit 52-year-old who died suddenly of a heart attack, having no obvious risk factors.

Then we see the opposite. There's always a red-meat eater out there who smokes like a chimney and lives to be 90.

What sense does it make?

So much of what medical science is telling us today is that how long we live, our susceptibility to disease, and even to depression, depend on our genes.

Not long ago, I spoke with a researcher at Kent State University who had studied the effects of exercise on our bodies and how genetics makes a difference. After that conversation, I understood why I never get bulging muscles no matter how much I work out. I need only look at my dad: He doesn't get bulging muscles either.

So then, if so much depends on our genetic makeup, is it even possible to make blanket statements about what's good for us or what's bad? How much depends on the genes?

Mladen Golubic, a molecular biologist and medical researcher at the Cleveland Clinic Foundation, talked about this during a lecture, titled "Diet, Genes and Cancer" at the Mustard Seed Market in Montrose near Akron, Ohio.

He used fish oil as an example _ something often touted as healthful. The evidence on whether fish oil is beneficial is conflicting, he said. It may be that different people respond differently, depending on genetics and how much of a particular kind of pro-inflammatory protein each person produces.

"What you have to do is look at the total evidence," Golubic said. "You have to look for consistencies. What is really the most consistent finding is that diets high in fruits and vegetables are protective against cancer and other disease. One-third of cancer can be avoided by not smoking. Another third can be avoided by diet."

According to studies, about 20 percent of the cancer cases relate to genetics and about 80 percent to environment. Some people are highly susceptible; others highly resistant. The vast majority, however, fall in the middle. That is where diet, exercise and other environmental factors can make a huge difference. You're in a high-risk environment, Golubic said, if your diet is high in meat, low in vegetables, your physical activity is low and you manage stress poorly.

"It's like a lottery," he said. "We're just starting to understand why some people are protected and others are not. But we know that if you move into a high-risk environment, you are more likely to develop disease, even having the best possible set of genes. Lifestyle factors are very important."

That seems to hold true even for those most susceptible.

We see the benefits of diet and exercise in heart patients, for example.

The journal Science published results of a new study relating to women who are genetically predisposed to breast cancer. Those who exercised regularly and avoided obesity as teens developed breast cancer later in life than those who had been overweight or inactive.

Who are we?

Oh, so much alike. Yet so different.

Maybe none of these new discoveries should surprise us. We already know that some can sing; others can't carry a tune. Some can throw a ball so it soars; others can't hit a target.

These little specialized skills _ and the fact that no one is good at everything _ make us dependent on each other. One person has the right makeup to be a nurse. Another a teacher. Another an engineer. Somehow it all fits together to make up the whole of the human race.