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The Oracle of DNA

Nancy S. Wexler

Molecular Genetics of Neuromuscular Disease
L.P. Rowland, Editor
Oxford University Press
1989

From the beginning of human history people have sought to tame the unpredictable through reading the future. Bones, stones, tea leaves, dice, cards, entrails -- all manner of animate and inanimate objects have been used to describe the shape of the future by the shape of their castings. Fortune-tellers with crystal balls or Tarot cards, shamans high on hallucinogens, wizards, witches, and soothsayers have been revered in all cultures and epochs.

As vaunted as the clairvoyants may be, their messages are often cryptic and hard to decipher. The Greeks refused to act on any important mission without first consulting the Oracle of Delphi. And yet tragedy often befell them. Macbeth's misunderstanding of the witches' prophesies to him led to his overweening arrogance and downfall. Those who open the doors to the future do not necessarily also provide their consultees with the wisdom to use foreknowledge constructively.

The critical question placed most often before the oracles, ancient and modern, is, at some elemental level, "Am I going to live or die on this mission? When and how will I die? Will I suffer?" People are mesmerized by the question and terrified of the answer. And yet many people have an internal sense of when and how they will die based on what they see happening to their relatives, particularly their parents and grandparents. If you ask people how old they will be when they die, they will readily answer, "Very old, because all of my relatives lived into their nineties," or "I feel I must live in a frenzy now because all of my relatives died of heart attacks before age forty." People use genetic prophesy on a daily basis.

And so it would appear that, in the elegant organization of nucleotide bases along the double helical spine, the die is really cast. But perhaps not forever.

PROPHESY WITHOUT PREVENTION

The recent spate of astonishing genetic discoveries in this era of recombinant DNA now finds us in a unique quandary. We are in the problematic position of being able to identify those who carry genes for fatal or crippling conditions without being able to prevent or treat the diseases.

Since 1983 genes have been located for Huntington disease, Duchenne muscular dystrophy, polycystic kidney disease, cystic fibrosis, phenylketonuria (PKU), manic depression, Alzheimer disease, and two forms of neurofibromatosis. The same strategies are being brought to bear to search for other genes such as those for schizophrenia, familial amyotrophic lateral sclerosis, dystonia, some cancers, alcoholism, Tourette syndrome, and others -- all disorders for which there is either no treatment or inadequate treatment. The expectation is that once the genetic lesion is characterized, effective treatments can be developed and genetic techniques can be used to intervene in the gene itself to ameliorate or cure the disease. Genetic research must follow a linear order from choromosomal localization of the gene to therapy. The anticipated benefits would also follow a certain order, from diagnosis to eradication of the disease. For most genetic investigators, the capacity to diagnose is merely a way-station along the road to a cure. And yet now, for patients and families, for physicians, for employers and insurance companies, and for the community at large, we find ourselves in the terrifying position of being able to predict severe disability or certain death without being able to prevent or treat it.

For some conditions, early diagnostic information can bring substantial gains. Children on controlled diets to prevent PKU thrive with an intact IQ. Physicians, apprised before or just after a birth that a baby has cystic fibrosis or sickle cell anemia, are likely to intervene vigorously with antibiotics or other medication in attempts to stave off some of the severe sequelae of those diseases. Even familial hypercholesterolemia is more manageable with new drug treatments that were developed as a direct result of basic work in molecular biology to understand the primary gene lesions.

For the most part, however, genetic diagnostic tests can be used in many more situations than we have recourse to treatment. They can be used prenatally with the aim of terminating a pregnancy in which the health of the fetus is seriously compromised, or to predict future disability in an asymptomatic individual. The most disquieting dilemma provoked by genetic advances is the capacity to prophesy before we can prevent. During this painful hiatus in science, when one breakthrough has been accomplished, making it possible to detect the abnormal gene, but the second breakthrough leading to treatment is still in the offing, we are challenged with all manner of psychological, social, ethical, and moral questions.

Genetic prediction has consequences for the individual, the family, and society. The gravity of these consequences and the choices they provoke differ depending upon (1) whether the inheritance pattern is dominant or recessive, (2) age at onset of symptoms, (3) if the disease is treatable, (4) the gravity, burden, and subjective perception for the disease, and (5) the symptoms, particularly if there is loss of mental capacities.

DOMINANT VERSUS RECESSIVE

If a disorder is recessive, such as Tay-Sachs disease or cystic fibrosis, the capacity for early diagnosis is relevant primarily for prenatal or perinatal diagnosis. Carrier parents can choose not to conceive, knowing they are carriers, or to complete only pregnancies in which the fetus does not carry two copies of the disease-producing allele.

Our ability to use DNA markers to detect carriers of cystic fibrosis is newly acquired. Many more people are confronted with the possibility of prenatal diagnosis for a different kind of disease than we are accustomed to detecting prenatally. Children with cystic fibrosis can now live moderately normal lives into the twenties and thirties. And parents are having to make choices not previously available. Nevertheless, the parents are only carriers and they will never be diagnosed with the disease. Their concern about cystic fibrosis is for their children.

If the illness is inherited in a dominant fashion, the "healthy," or asymptomatic individual, is being diagnosed with an illness that will appear in the future, sometimes many years later. If the diagnostic test is used prenatally, a positive diagnosis in the fetus immediately diagnoses the parent.

Huntington disease is the first autosomal dominant, late- onset, severe disorder for which a DNA marker, tightly linked to the disease gene (on chromosome 4) now permits presymptomatic diagnosis (1). There also seems to be little or no significant genetic heterogeneity that might preclude widespread use of the test. About 75 families worldwide have been tested and share the same Huntington disease locus (2).

In 1987, markers localizing genes for familial Alzheimer disease (3) and two forms of manic-depressive disorder were discovered (one on chromosome 11 and one X-linked) (4,5). In these conditions, genetic heterogeneity is likely to play a major role, complicating diagnostic testing by requiring probes that are specific for a particular subset of families. Variable penetrance, particularly with respect to manic depression, gives counseling a unique twist. Should people be told they are most likely carrying a gene for predisposition to manic-depressive illness, when (at least in the form found on chromosome 11) there is only a 63% penetrance rate (4)? How will people interpret a 63/37 risk -- perhaps as 50/50 or 100%? Will anticipating the illness precipitate it? Should phrophylactic lithium therapy be given even though there is a large chance that the person will never become symptomatic?

In some conditions, knowledge of vulnerability to a late- onset illness may help a person to receive immediately appropriate treatment once symptoms appear, and may even preclude some complications that might be induced iatrogenically. For example, bipolar illness may begin with unipolar symptoms that are treated with tricyclic antidepressants. There is evidence that these medications may actually exacerbate the cycling pattern once the bipolar phase begins (6). It might be advisable to avoid these drugs in people who are genetically vulnerable to bipolar manic-depressive disorder.

HUNTINGTON DISEASE AS A MODEL FOR PRESYMPTOMATIC DIAGNOSIS

Huntington disease and familial Alzheimer disease are both autosomal dominant, neurodegenerative disorders of late onset, invariably untreatable. The presymptomatic test for Huntington disease, using DNA probes approximately 4 cM (four million base pairs) from the defective gene, is now being offered under strict research protocols in several locales (Harvard, Johns Hopkins, and Columbia Universities, University of British Columbia, Canada, and Universities of Manchester and Cardiff, England). In the 2 years since the test became clinically available, about 100 individuals worldwide have received diagnostic information. Some people were already symptomatic when they came for the test and they were diagnosed clinically. Others changed their minds and postponed testing until treatment becomes available, or the test is 100% accurate. Some decided they would prefer not to receive any predictive information.

Centers offering the test have been impressed by the low response rate of persons at risk to avail themselves of the test. In all three centers in the United States, serving an at risk population in the thousands, fewer than 200 individuals have actually enrolled in a testing program (7). These findings are in sharp contrast to the enthusiastic response to testing that was found before the test was actually available. In several surveys over the past decade, between 63% and 79% of the at risk respondents said they would take a presymptomatic test (8-11). Obviously, the reality of the test, particularly a linkage test that involves other family members and is not entirely accurate, is less appealing than the prospect.

Psychologists Kahneman and Tversky offer some insight into this seeming change of opinion (although it is probably still too early to tell) (12,13). They argue that people are not adverse to taking risks but are rather adverse to taking losses. If they perceive that they have an advantage, however small, they tend to be conservative rather than gambling to achieve a greater gain at the risk of losing everything -- the "bird in hand" philosophy. On the other hand, if people perceive themselves to be already in a loss situation, they will gamble to escape the loss, even if it means they may lose more. If they are already down, the argument goes, what does a little more mean if it is possible not to lose anything. The same situations, described either in terms of losses or gains, can provoke opposite responses in the same people. Genetic counselors know this phenomenon well, taking pains to emphasize balanced phraseologies for risk, for example, "You have 3 in 4 chances to have a normal baby" (gain) and "You have a 1 in 4 chance to have a genetically defective baby" (loss).

If people coming for the presymptomatic test for Huntington disease perceive themselves to be in a loss position because they are at risk, if being at risk has hampered their lives tremendously, they will be willing to risk a terrible loss - - hearing that they most likely have Huntington disease -- for the gain of learning they are gene free. If, in contrast, people have been relatively happy when they come for testing, they may realize that the increment of satisfaction or relief brought by a negative test would not outweigh the disastrousness of presymptomatic diagnosis. People who want the test are more likely to perceive themselves already in a loss position and are willing to gamble. Those who see themselves already in a gain position fear that they have a lot to lose with a bad outcome of the test. A large part of the counseling is in helping people to realize more clearly what they stand to gain or lose with different test outcomes.

For many who receive a high probability of being gene free, the good news is tempered with concern for siblings and other relatives. For those who learn that they have a high probability of having the Huntington disease gene and are likely to become ill at some indeterminate time in the future, the information is devastating. Some have said that no matter how prepared they thought they were, they could not imagine beforehand how it would be as a reality. And it was much worse than they had thought (14). The only suicide attempt was made by a person who came for presymptomatic testing and, instead, was diagnosed clinically (15).

Nevertheless, a presymptomatic test for Huntington disease does provide some obvious benefits. Individuals "at risk" can plan for marriage, career, finances, and, most particularly, children, knowing in advance if all is likely to be jeopardized. Those with a lowered risk could stop being hypervigilant for symptoms, as many are, whereas those carrying the gene would undoubtedly find themselves constantly screening themselves for the first signs. The test gives no indication when symptoms will appear, so the insidious onset of minute disturbances in movement, memory, and mood can bring wracking uncertainty even to probable gene carriers. Many who wish to take the test want to resolve the ambiguity of being at risk, for better or worse. They cannot abide not knowing how to interpret minor adventitious movements, moodiness, and depression, or difficulties at work or in personal relationships. There is a danger that these people are seeking desperately to learn that they do not have the illness but are not truly prepared to learn that they do carry the gene. If they have a positive test, the ambiguity of waiting for disease onset may be unbearable and they could decide to become patients as a kind of riddance phenomenon, foreclosing on possibly years of health.

The advent of a presymptomatic test for Huntington disease using DNA markers has led to a new category of individual: the presymptomatic person with the Huntington disease gene. Not yet a patient, no longer at risk, how does this person live? Many Huntington disease patients have had long and productive lives, families, and careers in all areas of endeavor, including medicine, law, academics, the military, construction, and others. Will a young person, age 21, with a 96% probability of carrying the gene, be willing to expend the time, money, and energy on developing a career? Will future patients shy away from taxing professions, be intimidated by the failures that are inevitable in any pursuit, doubt their own abilities, and abandon pathways that could make their lives rewarding while they are still young and healthy? Will physicians, parents, friends, and relatives discourage them from pursuing careers they could not sustain once they become ill? Will universities and employers refuse to accept the presymptomatic individual if this status is known?

What is the diagnosed individual's social and ethical responsibility? What if a neurosurgeon, a pilot, or a stockbroker tests positively for the likely presence of the gene. Should they stop working immediately? How do they monitor themselves adequately? Should those around presymptomatic persons in potentially high risk jobs, to themselves or others, try to dissuade them from continuing these activities? Although neurosurgery under the knife of someone at risk may be acceptable, knowing the diabolic gene is present -- a gene that causes the tiniest uncontrollable movements of fingers, the most fleeting lapses of memory and judgment -- should someone intervene and prevent the surgeon from operating? Should the surgeon's continuation with his or her job be considered such a failure of good judgment that the disease must certainly be starting? Many of these same concerns will be true when a test for familial Alzheimer disease is also available.

Prenatal testing for Huntington disease offers some relief from a few of the quandaries posed by presymptomatic testing but introduces other twists. At risk parents might want to ensure that their children are free from the Huntington disease gene without learning their own genotype. If so, they can test fetuses. In three of four instances, the fetus should be negative for the haplotype that indicates the presence of the disease gene. The at risk parent's genotype is unknown -- unless the fetus tests positively.

If an at risk parent wants to avoid any chance of learning his or her genotype inadvertently through testing the child, or perhaps there are too few family members to determine his or her genotype, a "nondisclosing" prenatal test can be offered. If the fetus inherits a chromosome 4 from an unaffected grandparent, spouse of the symptomatic patient, the risk of the fetus is 2%. If the fetus inherits a chromosome 4 from the affected grandparent, the risk if 50%, or the same risk as the parent. It is not known if the chromosome 4 from the affected grandparent is carrying the healthy or lethal allele. The genotype of the at risk parent is not required for this test.

All centers that offer tests for Huntington disease make the test available only to persons age 18 or older who can give an informed consent. Current opinion is that parents should not be privy to this knowledge for their minor children. A disturbing ethical problem is raised by prenatal testing. Sometimes, a fetus is tested, found to be at 50% risk, and the parents decide not to terminate the pregnancy. If the at risk parent develops Huntington disease, the genotype of the tested child is also known because they share the same chromosome 4 (barring recombinations). A minor child has thus been de facto tested presymptomatically. And yet, programs cannot insist that couples abort children who are found to have a 50% risk. Sage counseling is needed to determine the intentions of prospective parents who want prenatal testing and to apprise them of these dilemmas.

Some argue that presymptomatic tests of this nature should not be used until treatment is also available. The potency of knowledge, for benefit or harm, has been an issue since Adam and Eve and the apple. Will genetic tests once more expunge us from the blissful ignorance of the Garden of Eden?

Sophocles grappled with the dreadful consequences of acts committed knowingly or unwittingly in Oedipus Rex. As the blind seer, Teiresias (many of those who see the future are blind to the present -- as if what they see is so powerful it robs them of ordinary sight), is summoned by Oedipus to explain why Thebes is sinking into putrefaction and decline; Teiresias realizes what devastating message he must deliver to Oedipus about his own actions: Teiresias: "Ah me! It is but sorrow to be wise when wisdom profits not." And later, after refusing to speak: "Though I hide all in silence, all will come" (16).

Finally Teiresias is goaded into revealing the truth, which propels Oedipus' wife Jocasta to suicide, and sends Oedipus, after stabbing his eyes out with Jocasta's broaches, reeling broken and alone into exile and perpetual night.

In all likelihood, revelations of genetic truths will not have such dire consequences. Appropriate counseling before and after receipt of genetic information is absolutely essential. In our society there is another hazard in making these tests available: there is little or no reimbursement from insurance companies for either genetic or psychological counseling. Genetic counselors do not usually see clients on a long-term basis and most are not trained as psychotherapists. Admission to a psychiatric hospital is almost the only mental health service for which there is insurance coverage. The person tested must pay for psychotherapeutic help for decision making before testing or follow-up after test results are delivered.

PRENATAL PREDICTION: COMPASSION OR CONVENIENCE?

Our increasing capacity to test prenatally for hereditary disease provokes some of the most trenchant questions. With prenatal detection increasingly possible, larger numbers of couples will be offered the possibility to know, before the birth of their child, if it is carrying a genetic defect. One immediate impediment in taking advantage of this information is the lack of understanding in the general public of genetic concepts and probability theory. Sadly, the public is joined in this ignorance by many physicians because of the woeful paucity of genetics teaching in medical school (17). As of 1985, only 18% of United States medical schools had genetics courses (17). Two years later, 24% were considered to have good or excellent instruction (18). There is little in the general medical school curriculum on genetics, small emphasis in practice, and a resulting inability among practitioners to interpret genetic tests or provide adequate counseling (17). In one survey, only half of the pediatricians and family practitioners could properly interpret a PKU test result (19). Medical malpractice suits may eventually make doctors more aware of their obligations to provide adequate genetic information to their patients, but we can hope that genetic awareness will not be born in the courts.

Some individuals will not wish to avail themselves of new genetic prenatal information because they are opposed to abortion under any circumstances. In the United States, however, over 80% of the population approves the use of abortion if the child will suffer deformities or death (20). In this new genetic terrain, prospective parents are mapping fresh landscapes. What if prenatal testing is done for a disease of late onset? Should there be an abortion for a fetus destined to become ill at age 40? age 80? What is the quality of the years "at risk" for someone knowing that this is their destiny? Children with cystic fibrosis are leading increasingly longer lives. Is this sufficient reason not to abort?

Some suggest that the new genetic and reproductive technologies being developed are also leading to the "commodification" of parenthood (21). Sperm, eggs, uteruses, bodies, and children can be bought and sold, rented and returned like so many dry goods. But the tremendous efforts expended, the expense, and the time and energy devoted to becoming parents also speak to a yearning for parenthood that is no longer impeded by biological constraints.

One fear, expressed cogently by Barbara Katz Rothman in her book The Tentative Pregnancy, is that with our increased capacity to screen prenatally for genetic defects, couples will insist on "the perfect baby" -- which still cannot be delivered.

An irony in all this is that the technology still cannot guarantee a "blue ribbon baby." A fetus can pass all of the tests and still be far from perfect at birth. A child can be born or become retarded, disabled, disfigured from thousands of causes. One can rationally decide to abort a fetus with spina bifida because life in a wheelchair is not acceptable -- and then have a baby's back broken in a car accident. One can choose not to carry to term a fetus with Down syndrome because the quality of life of the retarded is not acceptable -- and then have the baby suffer permanent brain damage from some illness. There are limits to control, and our children are always "hostages to fortune." Does the conscious, deliberate emphasis on control and "standards of acceptability" prepare us for the reality of parenthood? (22)

There is a crucial element missing in this rather materialistic analysis of parental motivations -- the parents' empathy with their handicapped or ill child. Many parents realize that life is so full of unexpected, uncontrollable wounds, such as auto accidents or disease, that they would prefer their children to start out as best prepared, body and mind, as possible. Frequently, prospective parents are quite familiar with the diseases for which they are testing their fetuses. They have seen these diseases face to face and are terrified of them. A previous child may have died a horrifying, deteriorative death -- a parent, a brother, or an uncle may have succumbed. Parents cannot bear to inflict this same torture on children they love. They cannot tolerate the idea that their own wish to have a child could cause untold suffering for that child, even if the child makes a good adaptation to its plight. Parents who use genetic services are not necessarily grocery store "aficionados," shopping for the perfect tomato. Rather, they are desperate to protect their children from harm; this may mean terminating a pregnancy before the fetus is viable to prevent later trauma for that child. Some would even argue that not terminating the pregnancy of a genetically impaired fetus, insisting knowingly that the child be born handicapped, is tantamount to child abuse.

In this light, the question of how long a life must be before it is worth bringing it into this world is irrelevant. The amount of time before death is not the issue; rather, it is the prospective parent's personal idiosyncratic view of the disease, how devastating it is, how much their child might suffer -- as a child or an adult. Just as parents want to give their children everything that they never had, for narcissistic as well as generous motivations, so too they want to spare them from the pain they have suffered.

A potential hazard in our expanding capacity to diagnose more disorders in the carrier state and prenatally is the parents' loss of innocence. Parents will find it increasingly difficult to plunge ahead with a pregnancy and take the consequences. It will soon become mandatory for physicians to offer the option of testing, at least for certain conditions, or if there is a known risk. A new law in California, for example, now requires physicians to screen for maternal serum a-fetoprotein to detect neural tube abnormalities. Pregnant women can refuse the test only by signing a waiver of liability. Doctors who do not offer amniocentesis to pregnant women over age 35 are liable for malpractice suits because amniocentesis is now standard medical practice.

With court-ordered loss of innocence, parents will be confronted with increasingly more complex choices and culpability. If they choose not to avail themselves of services offered, they are responsible for any abnormalities the child might bear. In electing not to detect prenatally, they are more actively visiting potential suffering on their children.

Rothman foresees that subtle or overt pressure may be brought to bear on parents who do not avail themselves of these services or do not terminate an abnormal fetus. Knowing of a family history of a particular disorder, insurance companies might require such testing and refuse to pay the medical costs for a defective baby. Physicians may bring increasing pressure on parents, citing the immense emotional and financial burdens on the family, suffering of other siblings, and costs to society for the care of abnormal children. Family and friends may also weigh in to persuade a couple to terminate "defective" fetuses and try again for a better baby. Rothman cites the compulsion to choose the socially acceptable choice: "Amniocentesis and selective abortion, like embryo transplants, surrogate motherhood, and other new reproductive technology, are all being used to give the illusion of choice" (23). Rothman believes that society constrains the choices to be made by making certain choices more easily assimilable culturally.

Some prospective parents find the ambiguity of their circumstances particularly perplexing. If they are carriers for Duchenne muscular dystrophy, for example, they may feel as if aborting a child with this disease is tantamount to aborting a beloved brother or other relative. People at risk for Huntington disease sometimes feel "How can I abort someone who has the same risk as me?" To abort a child with the same genetic identity -- in one respect -- is confusingly close to denying the validity of your own identity. This argument is often voiced by members of handicapped rights groups who object to the promotion of abortion for conditions from which they suffer.

One of the more specious arguments against using new genetic technology is that we, as a culture, may lose certain heroes known to be afflicted by particular diseases. No Woody Guthrie, who died of Huntington disease, no Sylvia Plath, who died a suicide. Or perhaps we lose a category of people such as artists like Van Gogh, whose wellsprings of inspiration may be the same DNA flaws that cause them searing psychological distress. Yet, myriads of gametes are never fertilized, never born, and never mourned.

THE EUGENIC PROTEST

The most strident cautionary voice on the perils of genetic research and testing is that of Jeremy Rifkin, Director of the Center for Economic Trends (24). Rifkin carries the "commodification" argument to the extreme, arguing that modern parents are no more interested in the individuality of their children than are buyers of automobiles. In his 1985 book, Declaration of a Heretic (25), Rifkin explains that Galileo was a heretic not because of his radical scientific views but because he opposed the established church of his day. Today's "church" is our society's complacent acceptance of scientific technology, Rifkin argues; our "faith system," the scientific world view; and Nobel laureates, the new prelates of the scientific establishment Church. In titling his book, Rifkin modestly announces himself as a modern day Galileo, with important truths about the universe and new insights into the nature of reality and existence.

And what are these truths? Rifkin equates the atomic age with the genetic age, the bomb with the gene. Splitting the atom and deciphering the double helix are discoveries of equal import to him and equal potential for destruction. Rifkin sees all of scientific progress as a perilous descent down a rain soaked, muddy, "slippery slope" where footing can be lost at any moment, plunging us all into the new eugenics (25):

Once we decide to begin the process of human genetic engineering, there is really no logical place to stop. If diabetes, sickle cell anemia, and cancer are to be cured by altering the genetic make-up of an individual, why not proceed to other "disorders": myopia, color blindness, left-handedness? Indeed, what is to preclude a society from deciding that a certain skin color is a disorder? In fact, why would we ever say no to any alteration of the genetic code that might enhance the well-being of the individual or the species? It would be difficult to even imagine society rejecting any genetic modification that promised to improve, in some way, the performance of the human race. (26)

In one sentence Rifkin travels from left handedness (hardly a disorder) to presumably the ravages of cancer, swift and fatal heart attacks, and the lingering decrepitude of Huntington and Alzheimer disease. He asks if "guaranteeing our health is worth trading away our humanity" (27). How is our humanity enhanced by permitting the perpetuation of diseases that devastate body and mind? He sees it as our moral duty to carry our faulty genes into the future so that our children too, may suffer. Rifkin also seems never to have heard of, or at least taken seriously, the civil rights movement in this country. Nor does he feel we are genuinely capable of moving beyond the flirtation of our society in the early 1900s with eugenics when Charles B. Davenport was in residence at Cold Spring Harbor running the Eugenics Records Office, instead of James D. Watson with a team of creative molecular geneticists. Rifkin assumes a unanimity of definitions of perfection that are unlikely to exist, such as the choice of the ideal skin color. Most troublesome, Rifkin is particularly stingy in his willingness to concede that society as a whole and individuals within it are capable of making discriminatory choices, capable of expending major efforts to treat severely debilitating and life-threatening diseases, with whatever means, genetic or otherwise, and leaving minor irritations alone. They will have enough to do to cure the myriad diseases to which humans are subject; if society does not wish minor genetic tinkering, it should not support it financially.

Ironically, gene therapy is probably the most natural of modern therapeutics. Scientists are attempting to use the body's healthy genes, the natural genes, to fix nature gone awry. By placing a normal hemoglobin gene in bone marrow stem cells, scientists are mimicking the normal state. If a way can be found to replace lost cancer suppressor genes or switch off genes undergoing abnormal amplification, children may not lose eyes to retinoblastoma, nor would other cancer patients be subjected to the devastating chemicals and blasts of radiation that are today's therapy but kill more than the intended targets. Furthermore, all current gene therapy research for humans is aimed at somatic therapy rather than germline therapy, curing patients rather than their progeny.

LEGAL ACCOUNTABILITY: WRONGFUL LIFE SUITS

Support for amniocentesis and selective abortion, in the absence of gene therapy, may come from an unexpected direction. Using a tort action known as wrongful life, children born with genetic defects have sometimes sued physicians whose duty it was to warn parents of potential genetic conditions. At first these cases were not accepted for legal action because the courts could not measure the value of a life lived or unlived. However, some cases are now being heard, although none has been won yet by the plaintiff (28).

These cases differ from typical malpractice cases because they presume that a person's life should never have existed at all, if the defendant had done his or her duty. To date, a wrongful life action has not been brought by a child against parents. In the past, children were constrained from suing parents, but courts now permit cases that involve property and finance (29). In 1987, an Illinois appeals court ruled that a 5-year-old girl, injured in a car accident while still in her mother's womb, could sue her mother for negligence (30). If a child born with severe deformities or a genetic defect decided that the parents could have detected the disorder prenatally, a suit against the parents might be based on wrongful life or negligence. Justice Oliver Wendell Holmes wrote a legal opinion in the late 1880s stating that there is "a conditional, prospective liability for one not yet in being" (31). Later courts have argued that every child has a right to begin life with physical and mental health (32). Marjorie Shaw, M.D., J.D., an expert in law as it pertains to genetics, has concluded that

knowingly, capriciously, or negligently transmitting a defective gene that causes pain and suffering and an agonizing death to an offspring is certainly a moral wrong if not a legal wrong. Thus, if reproduction is contemplated (or not consciously prevented) there is an ethical obligation not to harm the offspring and one's genotype should be determined so that appropriate steps can be taken to avert the disease in future generations. (33)

Pressures on parents to use genetic services will certainly, in part, be considerations of ethical duty to the child and responsibility to society. Parents might also choose to do what is most convenient for them, feeling themselves incapable of or unwilling to raise a handicapped child. But the moral and ethical responsibilities of the parents to do no harm to their children may yet be reinforced by court actions. After all, the children suffer the handicaps, not the parents.

CONFIDENTIALITY AND OTHER CONSIDERATIONS

The noisy debate over eugenics threatens to obscure some difficult and immediate problems. Many individuals do not wish to have third party carriers pay for their genetic tests because the carriers cannot guarantee confidentiality of the results. If insurance companies know that someone has had a positive test for having a high probability of developing Huntington disease, Alzheimer disease, or some other devastating disorder of late onset, there is a grave risk that the insurance policy will be canceled (34). Insurance companies have not yet acted to make a predisposing gene equivalent to a preexisting condition that would nullify a contract. If third-party carriers do not pay for the expensive genetic tests, however, few people will be able to afford them. Genetic testing will be the prerogative of only the wealthy.

The use of genetic tests for screening in the workplace is another potential source of abuse. One biotechnology company, Focus Technologies, is developing a panel of genetic tests that could be used by employers to screen employees (35). Employers might altruistically be saving employees from potentially hazardous work environments, but they may also be trying to reduce the company's health care costs or to avoid spending the money necessary to make an environment safe for the genetically vulnerable.

Similarly, a predisposing gene might be seen as grounds for dismissal rather than grounds for receiving improved medical care. For example, an employee with a gene for familial hypercholesterolemia should not be taken off the job for fear of a sudden heart attack, but rather should have periodic tests of blood cholesterol levels. More difficult to contend with is the employer's response to people with genes predisposing to psychiatric disorders. Routine health checks are not easy in these circumstances. And the company, like the family, cannot be seen as hovering over the genetically vulnerable person, waiting "for the other shoe to drop." In some civil service or tenured positions, it is difficult to force employees to leave even if job performance is slipping. Employers can legally require genetic tests as a condition of employment; the employee is free to take the tests or leave -- a choice that is not viable in many small towns.

Proposed legislation has been designed to protect citizens from mandatory screening for the human immunosuppressive virus (HIV), for the maintenance of confidential records if tests are made, and for protection in employment. HIV legislation could also have unexpected benefits for people with genetic diseases (36). At the moment, the Rehabilitation Act of 1974 provides protection from discrimination against the handicapped, or those who "give the appearance of being handicapped." Persons who test positively for genes that predispose to particular disorders may be discriminated against even though they were not handicapped at the time of employment. The HIV and genetic disease constituencies should recognize that legislation beneficial or harmful for one group may have the same implications for the other group.

There are certainly many parallels between the testing programs for persons at risk for Huntington disease and HIV (37-40). Both disorders are sexually transmitted, although HIV poses a far greater risk to the community at large. Neither test is 100% accurate and both tell those with positive outcomes only that a disease is likely to appear at some unspecified time in the future. Both disorders produce dementia, are marginally treatable, and invariably fatal. There is a risk of discrimination and stigmatization to both groups (although far greater for HIV carriers) and both groups must struggle continuously with terrifying ambiguities and certainties. Both groups are in need of quick access to counseling for which they must pay personally.

MAPPING THE FUTURE

For the first time in history, the time is ripe for making major inroads on diseases that wreak havoc not only on one generation but on each subsequent generation. Through learning to understand and work with DNA, scientists can become healers at the most fundamental levels. Once we have the capacity to move ahead, however, if we choose not to, we are consigning some people to certain death as actively as if we were to withhold antibiotics or oxygen. The road is before us; we no longer have the excuse that there is nothing to be done. If we act recklessly on this road, we will also rue the consequences. At each step we must weigh and reaffirm our commitments -- particularly to the Hippocratic oath and to Galen's oath to do no harm. Acting in a responsible, thoughtful manner can bring freedom from suffering, pain, and fear in ways not yet imagined. The oracular vision is only as good as its human interpretation.

REFERENCES

1. Gusella JF, Wexler NS, Conneally PM, et al. A polymorphic DNA marker genetically linked to Huntington's disease. Nature (London) 1983; 306:234- 238.

2. Conneally PM, Wexler NW, Gusella JF. Genetic heterogeneity in Huntington's disease. 1988; in preparation.

3. St. George-Hyslop PH, Tanzi RE, Polinsky RJ, et al. The genetic defect causing familial Alzheimer's disease maps on chromosome 21. Science 1987; 235:885-887.

4. Egeland JA, Gerhard DS, Pauls D, et al. Linkage between a gene conferring predisposition to bipolar affective disorders and DNA markers on chromosome 11. Nature (London) 1987; 325:783-787.

5. Baron M, Risch N, Hamburger R, Mandel B, Kushner S, Newman M, Drumer D, Belmaker RH. Genetic linkage between X-chromosome markers and bipolar affective illness. Nature 1987; 326:289-292.

6. Potter D. Personal Communication (1986).

7. Myers R. Personal Communication (1987).

8. Kessler S, Field T, Worth L, Mosbarger H. Attitudes of persons at risk for Huntington disease toward predictive testing. Am J Med Genet 1987; 26:259-270.

9. Marker DS, Young AB, Penney JB. At-risk person's attitudes toward presymptomatic and prenatal testing of Huntington disease in Michigan. Am J Med Genet 1987; 26:295-305.

10. Mastromauro C, Myers RH, Berkman B. Attitudes toward presymptomatic testing in Huntington disease. Am J Med Genet 1987; 26:271-282.

11. Meissen GJ, Berchek RL. Intended use of predictive testing by those at risk for Huntington disease. Am J Med Genet 1987; 26:283-293.

12. Kahneman D, Tversky A. The psychology of preference. Sci Am 1982; 246:161-171.

13. Tversky A, Kahneman D. The framing of decisions and the psychology of choice. Science 1981; 211:453-458.

14. Myers R. Personal Communication (1987).

15. Hayden M. Personal Communication (1987).

16. Sophocles. Oedipus the King. In Eight Great Tragedies. New York: Mentor Books, 1957, pp 65-66.

17. Childs B, Huether CA, Murphy EA. Human genetics teaching in U.S. medical schools. Am J Hum Genet 1981; 33:1-10.

18. Schmickel R, et al. Unpublished paper prepared for the American Society of Human Genetics (Courtesy of NA Holtzman) (1987).

19. Holtzman NA, in preparation (1988).

20. Rothman BK. The Tentative Pregnancy. New York: Viking Press, 1986, p 3.

21. Ibid, p 2.

22. Ibid, p 7.

23. Ibid, p 14.

24. Rifkin J. Algeny: A New Word -- A New World. New York: Viking Press 1983.

25. Rifkin J. Declaration of a Heretic. Boston: Routledge & Kegan Paul, 1987, pp 4-6.

26. Ibid, pp 66-67.

27. Ibid, p 121.

28. Wexler NS. Will the circle be unbroken? Sterilizing the genetically impaired. In Milunsky A, ed. Genetics and the Law, Vol. 11. New York: Plenum Press, 1980.

 

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