Medical researchers are hailing an important step forward in diagnosing Alzheimer’s disease. Staff at Georgetown University in Washington, D.C., have developed a blood test that detects the ailment, three years before symptoms occur.
Yet the discovery, impressive as it is, brings with it a dilemma. There is currently no cure for Alzheimer’s. Drugs can slow the progress of the disease to a modest extent. And work is under way to create better forms of treatment — more of that below.
But as things stand, how many of us would wish to know, some years in advance, that such a future awaits?
This dilemma is not confined to Alzheimer’s. Children of a parent with Huntington’s disease have a one in four chance of inheriting the fatal condition. There is also a blood test for this ailment. How many of us would take it?
Women with the BRCA1 and 2 genes are more likely to develop breast cancer. Some opt for a preventive mastectomy rather than face the odds. Again, an agonizing choice.
These predicaments all stem from a revolution in health care — the rise of personalized medicine. With the human genome now fully mapped, it is becoming possible to predict illnesses that lie ahead for each of us, perhaps decades in our future. Blissful ignorance, increasingly, will be a thing of the past.
Of course, the ability to foresee the future also offers, in some cases, the ability to change it.
For more than two centuries, a group of families in Newfoundland suffered a history of sudden, inexplicable fatalities.
Seemingly fit men and women, many in their 20s and 30s, suddenly dropped dead for no apparent reason. Rosalie Cater’s brother Graham died at a restaurant at the age of 26. Her brother Terry collapsed and died on his back porch, aged 43. Her nephew, a teacher, fell to the floor and died in front of his students. He was 28.
An examination of family genomes revealed a mutation that interfered with heart function. With that knowledge, family members who shared the mutation were pre-emptively fitted with pacemakers. Over the years, every one of them has had the device fire at least once. Cater’s son Tim was saved when his defibrillator switched on while he was playing hockey.
At the University of B.C.’s new brain-research centre, the family history of 25,000 Alzheimer’s patients is being painstakingly assembled. A genetic mutation has been identified in some of the patients, and a new drug to neutralize the defect is undergoing clinical trials.
The medication, if it works, will be effective on only a small percentage of patients. But the expertise gained might lead to treatments with wider applications.
In theory, other neurological diseases such as Parkinson’s and multiple sclerosis, also cancer, and perhaps psychological ailments like depression, are susceptible to gene-based analysis and treatment.
These techniques are still in their infancy. There are many obstacles to overcome. But it seems inevitable that, over time, they will revolutionize the practice of medicine.
And they will change forever the way we live our lives. It is said that a little knowledge is a dangerous thing. With personalized medicine, we have the potential for a lot of information — perhaps more than we can easily handle.
Events that once seemed like bad luck will gradually become preventable. And insights of that kind will demand our attention.
Where this leads is anyone’s guess. But it seems probable that future generations will live far more watchful lives, with genetic counsellors to guide their decisions.
Our grandparents took comfort in the belief that sufficient to the day is the evil thereof.
In contrast, our children might have the anxiety of knowing exactly what evils await but also, we hope, the power to forestall them.
