Sequence of Events: Progressing Toward Personalized Medicine

If you are a regular reader of Crossroads, you may have heard about “personalized medicine.” What is it, and how does it apply to you? First of all, it is not some new way of treating patients with the niceties that should be a regular part of good medical care. (My personal gripe is those physicians who keep me waiting long after my appointment’s stated time. Sometimes there’s a reason, but often not. I have personally waited more than an hour only to discover as I left that my doctor had a personal appointment at the same time as mine. It apparently didn’t occur to him to call his office and alert me.) That is not what this is about, as important as prompt attention and other niceties are.            

This is about the changes that are beginning to happen now and will accelerate as our understanding of human genetics gains momentum.            

I recall those who didn’t believe we should start studying genetics even though Drs. James Watson and Francis Crick had already discovered DNA and how its four bases interact to make the specific genes that link together in our chromosomes. In fact, I was a member of the National Cancer Advisory Committee, appointed by President Ronald Reagan, that voted on Dr. Watson’s plan to sequence the human genome when it was first proposed. Many skeptics said it to be too difficult, too expensive and too time-consuming.

Fortunately, most of us thought that it would be worth the effort and expense. So we voted for it, and the National Cancer Institute had the courage to proceed down the road to personalized medicine. We are now beginning to see its earliest applications, including the discovery of a chromosome that plays the key role in the development of Down’s syndrome—an early example of visualizing a genetic variation associated with a specific disease. The field has exploded, and many institutions such as UAB now have genetics departments dedicated to researching personalized medicine.            

We have gone far beyond the initial faltering start. We have long ago sequenced the human genome. The NCI is now readying, under the leadership of Dr. Francis Collins, who identified the gene that causes cystic fibrosis, a National Institutes of Health program to sequence every gene; i.e., to determine the structure of every gene found in humans. In doing so, we will be able to determine when a given gene is normal or abnormal and then discover the effects of specific abnormalities.            

How will this be helpful? Learning how the genes in a particular cancer, for instance, differ from normal genes may lead to the development of drugs that can target and disable the abnormal genes. Knowing the role that genes play in the response to certain drugs may lead to treatment programs for previously resistant cancers and the creation of better therapeutic agents. Your treatment may be customized for you and differ from that given to someone else with the same disease—all because the diseases have different key genes that influence outcome, even though they look the same under a microscope.            

Hopes are high. The estimated time to complete the gene sequence is four years, and it will cost only $.01 for each sequence. And in the end, we may have many of the answers about the most difficult problem in biology: cancer.

John Durant, M.D.
Cancer Center Founding Director