August 21, 2003 (Ira Pilgrim)


If a man does not keep pace with his companions, perhaps it is because he hears a different drummer. Let him step to the music which he hears, however measured or far away.

Henry David Thoreau

Pick up any medical journal and there will be at least one article about a new drug and its effect on a group of people. I have never heard of a drug that had the same effect on all of the people tested. While the wonder drug aspirin will relieve minor pain, it will be more effective in some people than in others. It will cause stomach upset in some people and not in others. A rare few people are allergic to aspirin and can be killed by it.

The search for a drug or treatment where "one-size-fits-all" goes on. To date, none have been found that I know of because, with the exception of identical twins, no two people are alike. They don't look alike, nor do they react the same to most things.

I spent a good part of my life studying individuality in mice and people. They are related, because the principles that are discovered in one species can often be applied to other species.

The basis of biological individuality resides in the genes. The mapping of the human genome, that has been so heavily hyped in the media, is only a bare beginning. What remains is the immense task of finding out what each gene does.

Much of medical treatment today is based on some non-existent average human being. When you read that a drug is effective against a disease in 50% of the people who take it, you are not told why. You are not told because nobody knows. While that 50% may be the best that can be done in most cases, it still means that if you give that drug to 100 people, it may not work on 50 of them. What a waste! Making matters worse, most drugs have some undesirable side effects that may be dangerous.

What is now being done in experimental medicine with people, used to be done on "white mice." A cage of white mice haven't much in common with each other except that they are all mice and they are all white. Over the past 70 years, strains of mice have been bred brother to sister, so that, within a strain, the animals are so much alike that you can exchange skin grafts between them, or even organs, and they will not be rejected. In other words, it is almost like having a cage of identical individuals. There are several strains of mice in which 100% of the females will get breast cancer, 100% will get leukemia, and so on. With these animals, it is possible to learn something about the interplay between heredity and environment. But mice are not people and, while the principles discovered in animals can be applied to people, you can't expect a person to react to something in the same way as a mouse does.

In all likelihood, the discoveries about the genes will first be tested on mice and other animals, and then, later, applied to people. When this is done, it will become obvious that every gene has many variants. We won't have to worry about those genetic variants that cause the early death of the egg, sperm or embryo any more than we have to worry about the child that is not conceived. There will, however, be lots and lots of genes left that will be of vital concern because they cause a good deal of human suffering.

But don't hold your breath, because understanding heredity will take a hellovalot of time.

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