Test Identifies Those at Risk of Nerve Disease
The first test capable of predicting whether a person will develop an incurable disease in mid-life has been offered to children of Huntington’s disease patients, providing a poignant look at the human consequences of the emerging technology of genetic screening.
The controversial technique, which someday may predict such conditions as cancer and heart disease, has raised serious social and ethical questions--in particular, whether insurers and employers might use the results to deny people medical coverage or employment.
“We will soon be in the position to diagnose a whole host of disorders many years before their onset,” said Jason Brandt, a Huntington’s researcher. “The technology will be there and we need to learn how to use it for the good--to help people rather than harm them.”
In the new study, published today in the New England Journal of Medicine, researchers offered the test to 47 people, all adults living in New England. Because each had one parent with Huntington’s disease, each had a 50-50 chance of having inherited the gene for the progressive neurological condition.
The majority volunteered out of a “need to know”: The threat of the disease had pervaded their lives, they said. Some were curious for the sake of their children, their marriages, their careers. Others said they simply wanted to end the uncertainty.
More than a third withdrew without completing the study. Five more were found already to have become sick. Of those remaining, four tested positive, seven tested negative and seven are still awaiting results. For another five, the results were inconclusive.
“I think everybody has some ambivalence about seeking this test,” said Richard Myers of Boston University, a co-author of the study. “It’s both frightening and something that is an integral part of the decisions that they are facing every day in their lives.”
In the case of a treatable disease, such a test might make possible early intervention to slow its course, Myers noted. But there is no known treatment for Huntington’s, which affects one in 20,000 Americans, destroying cells at the center of the brain.
In Myers’ study, those found to be carrying the gene were shocked. They had more difficulty coping with the news than they had expected. They and their spouses experienced periods of severe depression; they found themselves re-evaluating work and marriage.
Time Eases Burden
After a year, their emotional response had diminished, according to the study. But the subjects became concerned that they were developing symptoms, such as mental deterioration. There have been no suicide attempts or hospitalizations, the researchers note.
Those who tested negative reported great relief--and tended to refer to the results as conclusive, although there is a small rate of error. Those with inconclusive results expressed frustration and disappointment, but also some relief at not having a positive result.
“We always ask people after, ‘Are you sorry you went ahead?’ ” said Brandt, who is running a related study at Johns Hopkins University. “. . . No one has said, ‘Yes, I’m sorry I did this.’ Instead, there is a feeling, ‘Now I know what to expect and I can make appropriate plans.’ ”
Nevertheless, such testing raises difficult questions that are likely to become increasingly pressing in coming years when, researchers say, it may become possible to test for more common conditions such as Alzheimer’s disease and some forms of cancer.
In particular, they are concerned about the psychological consequences of advance knowledge of an incurable condition, as well as whether insurers or employers might seek to use the tests to screen out people at risk.
Employers’ Costs
For example, employers might like to reduce the costs, absenteeism and turnover that come with employees who become seriously ill. Similarly, insurers might feel they had a right to any medical information that bears on a client’s life span or future health.
“The whole premise of insurance is that you’re sharing risks because of the unknown,” said Mark Rothstein, director of the Health Law Institute at the University of Houston. “If the unknown is suddenly known, what implications does that have for insurance?”
According to Rothstein, only four states have laws that regulate the use of genetic testing. In Florida, Louisiana and North Carolina, they apply only to testing for sickle-cell anemia. New Jersey’s law also covers cystic fibrosis, Tay-Sachs disease and thalassemia, he said.
Rothstein said it is unclear whether state and federal laws barring discrimination against the handicapped would protect people who will come down with an illness in the future.
Congressional Study
Later this month, the congressional Office of Technology Assessment expects to complete a study of the medical tests currently in use by employers and insurers, addressing in part emerging technologies such as genetic screening and their public policy implications.
“Frankly speaking, a company would really think twice before they instituted a program like this,” said Lawrence Miike,, the analyst in charge of the study. “Because I think the ruckus you raise is not worth it.”
