Genetic Testing for Alzheimer Disease: Ethical and Clinical Issues - Hardcover

Hardcover

ISBN 10: 0801858402 ISBN 13: 9780801858406

Publisher: The Johns Hopkins University Press, 1998

Synopsis

The genetics of Alzheimer disease has been a point of intense concern and immense informational confusion for families in which a loved one is diagnosed with dementia. In recent years, however, scientists have begun to uncover the genetic bases for some forms of Alzheimer disease. Once a chromosomal defect is identified, it becomes possible to devise a test for its presence. The far-reaching implications of such tests are the focus of the present volume.

In Genetic Testing for Alzheimer Disease, Stephen G. Post and Peter J. Whitehouse bring together experts from the fields of ethics, genetics, policy, neurology, philosophy, and anthropology to examine the ethical and social aspects of genetic testing for Alzheimer disease. The authors begin by focusing on current genetic findings and their clinical applicability. They then address ethical issues in genetic testing and genetic counseling for Alzheimer disease. They examine social issues such as confidentiality, discrimination, and fairness in health care. Finally, they discuss ways to educate professionals and laypeople regarding these issues.

Contributors: Robert H. Binstock, Ph.D.·Thomas D. Bird, M.D. · Robert Mullan Cook-Deegan, M.D.· Leonard Fleck, Ph.D. · Atwood D. Gaines, Ph.D, M.P.H. · Eric T. Juengst, Ph.D. · Harry Karlinsky, M.D. · Steven Miles, M.D. · Thomas H. Murray, Ph.D. · Stephen G. Post, Ph.D. · Kimberly A. Quaid, Ph.D. · Allen D. Roses, M.D. · Greg A. Sachs, M.D. · Peter H. St. George-Hyslop, M.D. · Bonnie Steinbock, Ph.D. · Arthur B. Zinn, M.D., Ph.D.

About this title

About the Author

Stephen G. Post, Ph.D., is an associate professor at the Center for Biomedical Ethics at the Case Western Reserve School of Medicine. He is the author of The Moral Challenge of Alzheimer Disease. Peter J. Whitehouse, M.D., Ph.D., is a professor of neurology at the CWRU Alzheimer Center at the Fairhill Center on Aging.

From The New England Journal of Medicine

As a geriatrician, I find that my name is sometimes mistakenly associated with the field of genetics, at least on lists of conferences or specialties. In the past, I gave no thought to these mistakes of alphabetical juxtaposition and just corrected the error, moving my name to the correct list. Moreover, it seemed that the two specialties could not be further apart, given that genetics deals mainly with diseases affecting children and geriatrics, obviously, with the opposite end of the age spectrum. But the truth is that because of the remarkable discoveries made over the past two decades in the genetics of Alzheimer's disease, these two specialties have begun to speak to each other. As a result, what would have been considered in the not-too-distant past a fanciful title for a symposium, "The Genetics of Geriatrics," seems not so strange anymore.

To oversimplify somewhat, in a very small proportion of patients with Alzheimer's disease (mainly younger patients), the pattern of inheritance is consistent with a single-gene disorder transmitted as a largely age-dependent, autosomal dominant trait. To date, three separate genes (one on chromosome 1, one on chromosome 14, and even more rare, one on chromosome 21) have been identified. For these unfortunate families, the classic method of genetic counseling worked out for other genetic diseases (e.g., Huntington's disease) can be used with little modification. However, most cases of Alzheimer's disease occur later in life, and thus the role of genetic factors, despite recent discoveries, remains murky. As is pointed out in the excellent introductory chapter, "Contrary to what some potential consumers of genetic testing believe, no predictive test for the typical late-onset (after age sixty-five) form of AD [Alzheimer's disease] exists. Only in a very few early-onset cases (before age fifty-five...) which constitute fewer than 1 or 2 percent of all AD cases, is predictive genetic testing possible."

The authors continue with what turns out to be a succinct summary of the book's message: "Thus, when the elderly person comes into the genetic testing clinic and asks for the AD predictive test, the only appropriate response is that the test does not yet exist." After this economical summary, the rest of the book is commentary, albeit a scientifically and ethically engaging exegesis.

This book brings together some of the foremost experts in the fields of dementia, genetics, ethics, and anthropology in Canada and the United States in an attempt to deal with the complex ethical and clinical issues relating to genetic testing for Alzheimer's disease. Although these subjects are discussed with great skill, a certain amount of repetition and contradiction inevitably occurs.

Happily, given the recent headlines about apolipoprotein E testing for Alzheimer's disease, this issue is discussed in detail. Beyond the negative opinion of its usefulness for prediction in the asymptomatic subject, the more justified use of this test in the differential diagnosis of cognitive impairment and the vexing question of its implications for research on presymptomatic disease are also thoughtfully addressed.

For those with an interest in the field of Alzheimer's disease from the clinical-research or ethical point of view, the entire book is worth reading, despite the repetition alluded to above. Parts should be of interest to generalists -- both family doctors and internists -- as well as cardiologists. All these physicians may elect to test their patients' apolipoprotein E for a reason related to cardiovascular health but may be asked questions about or feel the urge to expound on the implications of the test with respect to Alzheimer's disease. For the primary care physician, the main message of the book may be gleaned from reading the introductory chapter as well as one entitled "Education for a Too Hopeful Public."

The subjects discussed and the debates offered in this monograph provide a microcosmic analogue of the macrocosm of medicine today. As the millennium fast approaches, we see once again that the speed and depth of our scientific discoveries continue to outpace our ethical and clinical abilities to cope, especially with respect to the care of the elderly. This book's thoughtful approach to the fascinating yet complicated subject of genetic testing for Alzheimer's disease can serve as a model for the myriad other similar ethical and medical conflicts found today in modern medicine.

In contrast to my previous practice, the next time that I am mistakenly credited with being a member of the wrong specialty because of an alphabetical misstep, I shall pay closer attention. It seems that genetics has finally become relevant to geriatrics.

Reviewed by A. Mark Clarfield, M.D.
Copyright © 1999 Massachusetts Medical Society. All rights reserved. The New England Journal of Medicine is a registered trademark of the MMS.

About this edition

• Publisher: The Johns Hopkins University Press
• Publication date: 1998
• ISBN 10: 0801858402
• ISBN 13: 9780801858406
• Binding: Hardcover
• Edition number: 1
• Number of pages: 304
• Editor: Post PhD Dr. Stephen G., Whitehouse MD PhD Dr. Peter J.