Onward Genetic Soldiers : MAPPING OUR GENES The Genome Project and the Future of Medicine<i> By Lois Wingerson(E.P. Dutton: $19.95; 302 pp.; 0-525-24877-3) </i> : GENOME<i> By Jerry E. Bishop and Michael Waldholz (Simon & Schuster: $21.95; 351 pp.; 0-671-67094-8) </i>
Nearly everyone has pondered his or her genetic destiny, whether in childhood fantasies about growing up in rich or poor families or in adult stories about struggling against biological and social limitations. In the last decade, however, the fields of genetics and molecular biology have suggested that biology need not always be destiny.
As both of these accessible books vividly illustrate, new scientific insights into maladies such as Huntington’s disease and cystic fibrosis already are helping us battle inherited illness.
“Genome” opens as Milton Wexler, a distinguished Los Angeles psychoanalyst, informs his two accomplished daughters, Alice and Nancy, that their mother Leonore has been struck with Huntington’s disease, a degenerative disorder of the brain. Each child of a parent with Huntington’s disease has a 50-50 chance of developing the illness, whose symptoms--alterations of movement, mood and memory--usually begin in mid-life.
Jerry Bishop and Michael Waldholz, science reporters at the Wall Street Journal, chronicle the Wexler family’s response to this challenge: They started the Hereditary Disease Foundation to encourage basic research on Huntington’s disease and other genetic disorders, recruited previously uninvolved scientists (including this reviewer) to plan and execute such research, and organized a ground-breaking study of a huge family with Huntington’s disease that lives on the shores of Venezuela’s Lake Maracaibo.
As a result of the Wexlers’ efforts, Huntington’s disease, which once cast a glaring light on medicine’s inability to confront genetic illness, now symbolizes hope for the future. The location of the Huntington’s disease gene on the human genetic map was discovered in 1983, encouraging the subsequent mapping and even the actual isolation of genes for other diseases--including cystic fibrosis, which affects one in about 2,500 children born in the United States. Researchers hope that such information will lead to understanding and cures, but therapies based on such information are years--if not decades--away. Already, however, the molecular advances enable us to predict many of whom will be stricken.
Of course, such prognostic prowess is a mixed blessing. Some people at risk for a genetic disease want to know their status, and some do not. In “Mapping Our Genes,” free-lance science journalist Lois Wingerson tells the moving story of “Frances,” a highly educated young woman at risk for Huntington’s disease.
When Frances was 12 or 13, her father began acting strangely--suffering from gross memory lapses, ordering for the whole family at restaurants without asking what they wanted, prohibiting his children from having parties. Frances watched as her father was confined in a straitjacket and carried away to a series of hospitals.
Years later, just before Frances’ wedding, it was discovered that her father probably had been suffering from Huntington’s disease. Frances and her fiance went ahead with the wedding anyway, but when a test for the disease became available, Frances signed up. After weeks of postponed results, a doctor ushered her into a small room and told her she would not succumb to the disease: “Everything’s fine. It’s fine.”
Not unlike people told that they have been infected with AIDS virus, people diagnosed as possessors of the Huntington’s gene cannot know when the poised sword will strike. Facing such information requires immense internal strength as well as solid external support from family, friends and health professionals. The reader can only be scandalized by the practice of conveying such information by an indifferent phone call or form letter, as has often been the case for carriers of the AIDS virus. As predictive testing becomes increasingly available, the medical community must develop and enforce clear and empathic standards of practice.
“Mapping Our Genes” and “Genome” cover much the same ground--the search for the genes responsible for Huntington’s disease, cystic fibrosis, manic depressive illness and inherited cancers--and both convey the intellectual excitement of the chase.
Wingerson’s stories, however, are more compellingly personal and psychologically complex, capturing what James Watson has called “the contradictory pulls of ambition and the sense of fair play.” While Bishop and Waldholz focus on the rewards of scientific and medical team work, Wingerson’s stories illustrate the isolation of both scientists and family members. The humanity of Wingerson’s protagonists is thus more apparent, whether we are reading about Betty LeBlanc, a Cajun woman from Louisiana who helped researchers track the inheritance of a gene responsible for the neurological disease that struck her son, or Janet Egeland, a sociologist who for years studied the appearance of manic-depressive disease among the Old Order Amish. Both books chronicle scientists’ ambitious efforts to trace the human genetic legacy, which is encoded in the four building blocks (called bases) of DNA, just as the English language contains information encoded in the sequence of 26 letters.
A human being’s entire genetic inheritance (or genome) contains about 3 billion bases, organized into about 100,000 genes, each of which specifies the structure of a single protein. Most of the genome, however, does not specify protein structure, and much of our DNA may in fact represent the molecular equivalent of the human appendix--a vestige of evolutionary history.
Some variations in DNA sequence help produce nonfunctional proteins and may thus cause a genetic disease, but many are benign and merely contribute to the diversity we see in every species. Variations in the DNA of individuals within a species serve as the raw material for natural selection.
As Wingerson suggests in her comparison of current gene research to Columbus’ voyages, however, our journey through the human genome has only begun. Our society, she argues, is in the same position as that under King Ferdinand and Queen Isabella: aware that the world is likely to change, but vastly underestimating the degree of change and not knowing how much profit we stand to realize from it. After all, Spain’s investment in Columbus at first yielded only tobacco, popcorn and syphilis--far from the dreamed of trade route to India.
The ability to predict disease before symptoms actually appear raises a host of ethical and social issues. Should an insurance com- pany require someone at risk for Huntington’s disease to undergo a test before its policy can be approved? Should an airline com- pany be allowed to fire a working pilot with a genetic predisposition to heart attacks?
Surely the insights of molecular genetics can be put to better use than denying jobs to genetically limited adults. The newly announced technology of “curing” cells from cystic-fibrosis patients, for example, offers a glimpse into the bright future of gene-based therapies.
Perhaps we can finally move beyond simplistic notions of “good” and “bad” genes to a more complex and less deterministic view of the interactions among genes and between genes and the environment. As the authors of these new works reveal, we have made an excellent beginning.
