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Genetic diagnosis of human embryos.

On the top floor of the Gold Museum in Bogota, Colombia, visitors are ushered into a dark, windowless room; heavy doors are closed behind them. They stand in the darkness until gradually, like a ringed and rising sun, lights come on around them and they see they are surrounded by gold - glimmering, lustrous gold. Face masks, nose clips, amulets, and jewelry present a dazzling display of wealth and beauty.

We are at an analogous stage in medical genetics, when the lights come up and we marvel at the wealth of discoveries and what have been called "breathtaking" advances in DNA diagnosis. Experiments are underway to treat seriously ill patients with their own genetically corrected cells. More problematically, in vitro fertilization (IVF) clinics are either already analyzing egg cells for genetic defects or are poised shortly to begin DNA analysis of human embryos.

For all the worried talk about genetic engineering over the last two decades, it is surprising how quietly plans for the genetic diagnosis of human embryos have developed. The issues raised warrant careful examination: what needs are met through embryo diagnosis? Who bears responsibility for monitoring this technique? Under what overarching ethic should embryo diagnosis and, eventually, embryo therapy, be applied? What are the broader societal implications raised by the genetic diagnosis of human embryos?

The Rationale for Diagnosis

Preimplantation biopsies of human embryos are aimed at couples at high risk for having a child with a serious genetic disorder such as cystic fibrosis or Tay-Sachs disease but who will not terminate a pregnancy. A typical candidate is a couple who has one child with a serious disorder but who, for personal or religious reasons, will not undergo chorionic villus sampling (CVS) or amniocentesis and possible pregnancy termination. Traditionally, their options have been either to risk the birth of an affected child or not to conceive. Embryo biopsy gives the couple the third option of signing on with an IVF program and transferring to the wife's uterus only embryos deemed free from the genetic flaw.[1] Embryos can also be sexed in order to transfer only female embryos to couples at risk for passing a sex-linked genetic disease such as Duchenne muscular dystrophy.[2] Several IVF clinics here and abroad are offering preimplantation diagnosis or have set in motion institutional review of planned programs.[3]

Other motivations also underlie the effort to introduce embryo screening. Preimplantation diagnosis is part of a broader plan to reduce the prevalence of certain genetic diseases. Practitioners look at children with genetic disorders and, as one pediatrician said, "It is driving them crazy." He likened embryo diagnosis to the "ultimate measles vaccine": if we vaccinate children to prevent the spread of disease within a generation, should we not also discard embryos to avoid passing disease between generations? States the director of one IVF clinic, "The possibility of eliminating a fair number of genetic diseases by the end of the decade is exciting."

As IVF becomes more streamlined with extraction of eggs in the clinician's office, freezing of spare embryos, and improved implantation rates, screening of embryos presents an advantageous alternative to carrier or prenatal screening if the goal is eliminating lethal diseases. Arguably it is morally more acceptable to discard embryos than to abort pregnancies. Moreover, it allows a deleterious recessive gene to be eliminated from a family's genetic line. A second option is to use a donated embryo, but if IVF and embryo diagnosis are available, couples would probably prefer their own biological embryo.

Clinicians' more ambitious goal is to prevent disease by correcting genetic defects in embryos. Preimplantation diagnosis will prevent disease passively by discarding embryos with deleterious genes. Embryo therapy will prevent disease in a different way by treating genetic anomalies in embryos and then saving and transferring the embryos. Just as neonatologists use fetal therapy to fix defects detected through prenatal screening, so may specialists try embryo therapy in the future. For example, research aimed at correcting the CF gene in eggs is a not-too-distant possibility.[4] One clinic's draft consent form states that the embryo biopsy will "prevent genetic disease and... lay the foundation for site-specific gene therapy."

Nor should economic benefits be overlooked as a motivating factor behind the expected spread of preimplantation diagnosis. Although the targeted clientele is now couples at known risk who are so determined to avoid pregnancy termination that they will try repeated IVF attempts, we can predict that other groups will be targeted as well - some suggest preimplantation diagnosis could one day be a standard of care for women of advanced maternal age.[5]

The justification for routine embryo diagnosis in IVF is not difficult to imagine. If couples in IVF clinics plan to have CVS or amniocentesis anyway, it seems reasonable to examine embryos before transfer to avoid the potential trauma of a pregnancy termination, especially for couples with a history of loss due to infertility or for women over thirty-five who have special worries about chromosomal abnormalities. Couples need not wait weeks or months for the results of prenatal tests but can know at the outset that their embryos are free from major chromosomal or genetic disorders. The actual cost of embryo testing will be about the same as for fetal testing - $1,000 to $2,000. Even couples not planning on prenatal testing could see this as an attractive option. Deliberately discarding faulty embryos is arguably no worse than the constant threat in IVF of embryo loss due to biological fluke.

Thus, practitioners can present embryo diagnosis as a logical step for IVF couples planning on prenatal screening. The embryos are here, it can be said, why not test them now? Control over genetic screening remains in the IVF clinic, in contrast to present procedures, in which couples who conceive through IVF often go elsewhere for prenatal testing and care. Adding diagnosis to its IVF services can provide economic benefits for a clinic.

Although many practitioners are conservative in their predictions about the frequency and desirability of embryo testing, dreams can be ambitious. One practitioner, for example, visualizes a twenty-first century in which "sex will be for pleasure only" and conception will take place in the medical setting. To this practitioner, routine testing to secure healthy infants is a desirable future.

Embryo diagnosis will also receive an unwitting boost if access to abortion is curtailed by legislatures and courts. If it becomes difficult to terminate a pregnancy, embryo diagnosis will offer an alternative to prenatal screening. Moreover, laws defining life as beginning at the moment of conception provide a justification for embryo therapy. Whether intentionally or not, pro-life positions add to the pulse behind assisted conception, embryo diagnosis, and even therapy.

Questions for Policy Making

As with IVF, embryo freezing, and micromanipulation, a primary concern lies with the safety of the procedure. Embryo diagnosis has been studied systematically with mouse and other animal embryos. Ethical concerns about nontherapeutic research on human embryos, federal resistance to funding, and uncertainty about the legality of embryo experimentation mean that clinical application precedes systematic investigations on human embryos, although researchers study abnormal and donated normal embryos on an ad hoc basis in the U.S. and on a more systematic basis abroad.[6]

Another question relates to the accuracy of the procedure. Genetic diagnosis is complex, and the vast amount of new information from genomic studies will undoubtedly lead to premature conclusions. To suggest that disorders can be diagnosed in the human embryo when knowledge is till unfolding and the array of unknowns is great invites hubris, with weighty consequences for couples trying to have healthy children. The danger of both false positive and false negative results is real. A couple told their embryo has a genetic defect when in fact it does not will experience financial loss and emotional strain from IVF, although no one may ever know that a false positive result occurred. A couple told their embryo does not have the feared defect when in fact it does will be in a worse situation. If prenatal screening (generally a part of the embryo diagnosis research protocol) detects an affected fetus, the couple will either terminate the pregnancy after having been so motivated to avoid this that they tried a highly experimental procedure, or bear a child with the disease. That this might mean a couple will have two or more children with the same disorder magnifies the serious consequences of premature application of embryo diagnosis.

There are also concerns about the impact of embryo genetics on future generations. If embryo diagnosis becomes reasonably common for fatal disorders in which the child would not have grown up to procreate in the first place, the short-term impact will be minimal. If the range of tested disorders expands to include diseases that would not have precluded procreation, genetic diversity may be affected, though what effect this might ultimately have is not yet known. The same issue can be raised for prenatal screening (and pregnancy termination), but with an important difference: treatment of fetuses fixes the symptoms; treatment of embryos eliminates the gene.

Moreover, embryo diagnosis opens IVF to fertile couples. In vitro fertilization is expensive and rarely fully covered by insurance. Pregnancy rates remain low, the stress on couples is high, and hormonal hyperstimulation and egg extraction burden women physically. Embryo diagnosis is a window to new technological tinkering with reproduction that, while holding promise, opens the door to stress, discomfort, and expense for women in the short run and pressures for assisted conception as a standard procedure in the long run.

This new field opens virtually limitless possibilities for refining biopsy methods, expanding the range of disorders screened for, and correcting faulty genes. It also promises what Daniel Callahan calls the "ragged edge" of medical treatment and progress - smooth edge is impossible when every advance creates first one and then another need to be addressed and fixed.[7] In this respect, embryo diagnosis is not so different from other areas of medicine. But trying to smooth the ragged embryo edge is different in at least one important respect: embryo manipulations are not, medically speaking, essential, and are not the simplest way of reducing illness. In a day of shrinking medical resources, their place in the hierarchy of medical priorities is open to debate.

Diagnosing and treating the embryo has few political limits. At present the federal government cannot fund research involving human embryos, and efforts to set up a structure to discuss the implications of genetic manipulations have been unsuccessful. State laws mentioning the embryo or conception were generally passed with the abortion controversy in mind and fail to provide a framework for reasoned discussion about the means and ends of embryo manipulation. One cannot realistically expect anticipatory policy to be developed in the public sector. Still, the implications of embryo genetics are too novel, far-reaching, and intimately connected with the human condition to be permitted to rise silently and by habitual degrees.

In the absence of public policy, then, a three-pronged approach to the questions raised by embryo diagnosis is in order that will (1) incorporate societal introspection about the goals of embryo diagnosis, (2) build an identity for embryo diagnosis that will place responsibility for overseeing it, and (3) develop ethically sound clinic policies.

What Needs? How Met?

Ideally, embryo genetics will be ushered into society by a cautious citizenry willing to question the goals of this new field and resist the lure of options raising troublesome implications. Embryo diagnosis is not patient-driven in the same way as IVF, nor does it have the sense of urgency of techniques designed to improve the medical status of individuals with AIDS or other terminal diseases. Introspection, then, can take place before embryo diagnosis becomes widespread in clinical practice and without the frenetic quality that comes when an immediate physical need is at issue. A critical mind, in place at the outset of embryo genetics, will ask these questions: What needs are served by embarking on embryo genetics? What priorities do these needs have in our society? Is this the best way of meeting those needs?

Embryo diagnosis is presented as a service to couples, yet a careful look should be given to how well it will actually serve couples' interests. There's no evidence to indicate a groundswell of support for the procedure among at-risk couples. In contrast to IVF, where tens of thousands of women were ready for a technique to circumvent blocked fallopian tubes, the clientele for embryo diagnosis is likely, initially at any rate, to be more narrowly defined. The technique will, in a word, need to be marketed and sold to people who may not realize they can benefit from it.

To get an idea of need, one practitioner sent a questionnaire to 123 women who had had prenatal testing because of previously abnormal conceptions. Of the 47 percent who responded, the initial impression of half, upon reading a summary of preimplantation diagnosis, was that the technique was a moderate or excellent improvement over prenatal testing. Women whose previous prenatal tests revealed abnormalities were twice as likely as other women to believe this. When asked how many IVF/embryo diagnosis procedures they themselves would undergo, 45 percent said none. They were wary about low pregnancy and birth success rates in IVF, risk to embryo, and cost.[8]

Pending further study, one may conclude that embryo diagnosis will be some time in the making inasmuch as IVF, biopsy techniques, and genetic tests on single cells all need improvement. One may expect a prolonged experimental phase during which couples will try diagnosis under varying conditions. This happened with IVF, where the patients were highly motivated and had little choice but to try this "last hope" for biological parenthood. With genetic risk, an alternative exists in the form of prenatal screening (itself being refined to detect abnormalities earlier in the pregnancy). Thus, one must consider the needs both of couples trying embryo diagnosis in the experimental stages and those trying it after the procedure becomes standard medical protocol. The former will predictably occupy much of this decade and are of more immediate concern.

For couples recruited to IVF to take part in experimental protocols, embryo diagnosis will minimize uncertainty if they cannot face the stress of waiting for prenatal screening and its results. The benefit of a shortened period of uncertainty may be outweighed, however, by new uncertainties introduced by the procedure, not least those of IVF itself. As an experimental procedure, embryo diagnosis also introduces worries about the accuracy of the results. Couples trying it will consent to CVS or amniocentesis as a routine backup, which makes embryo diagnosis a somewhat illusory relief from prenatal screening.

Couples already in IVF programs may be recruited to embryo diagnosis through monetary enticements (such as no charge for the diagnosis). However, embryo diagnosis will bring new dilemmas for people whose central mission is to have a baby. It is thought that much of the embryo loss that occurs in IVF is related to chromosomal or genetic abnormalities, so that unbeknownst to anyone, unseen flaws doom the embryo to be sloughed from the body. This natural selection occurs without choice or knowledge. Very few couples confront the dilemma of whether to continue or terminate a pregnancy when an embryo with abnormalities has implanted because most such pregnancies abort spontaneously.

With embryo diagnosis, the number and nature of people facing choices changes. More people will be given news of embryo abnormalities than fetal abnormalities. Again, this will become progressively more problematic as the number of diagnosable abnormalities grows to include not just major maladies such as Down syndrome but also moderate disorders and predispositions to disease. In short, with embryo diagnosis couples who did not necessarily place a priority on screening are drawn into the net and face problematic decisions.

In vitro fertilization and its variations have opened conception to people with a range of infertility problems. Embryo diagnosis opens conception to people with genetic problems. Yet embryo genetics will make a dent, at most, on single-locus disorders affecting select groups of people in advanced industrial countries who can afford to pay for IVF and embryo diagnosis. As an exciting and innovative field, will it be pursued at the expense of other means of protecting children's health?

Moreover, if embryo diagnosis is marketed for more than at-risk couples, it win take on a momentum of its own, leading to spiraling created needs, among other things, to have a supposedly risk-free pregnancy and birth (even though genetic mutations and teratogenic influences during pregnancy preclude the certainty of a healthftul birth). Ultimately, genetically at-risk couples, such as carriers of the Tay-Sachs gene, may be only a small segment of the prospective clientele.

A type of affirmative action is in the works in which steps can be taken to help diverse groups of people have a child. This pushes procreation into the public arena and thus fosters an intense interest in fixing the numerous stages in reproduction where something can go wrong. Recent reports of high rates of chromosomal defects in eggs, sperm, and embryos inspire a problem-solving mode, a drive to fix conditions once thought natural, if unfortunate, or not even recognized as problems. With knowledge comes a widening of those deemed "at risk," which in turn leads to more needs to diagnose and fix. Far from recruiting more people to get help in conception, however, the opposite result might happen, inasmuch as couples faced with an expensive and complicated act of conception may simply remove themselves from the process and decide not to have children at all. The net gain of numbers of children born to high risk couples may not be as great as expected after all.

The lead time between theory and practice has narrowed to the point where discussion of ends and means is needed now. Beneath the excitement of embryo genetics lie fears that are shunted aside rather than confronted - the fear of having a child with an anomaly, the fear of being responsible for letting a child be born with a disorder, the fear of having disabled children in the society, and practitioners' fear of being left behind if they do not add embryo genetics to their list of services. Various needs are being cloaked by the addition of a new set of reproductive technologies. The impetus for the new genetics does not seem to be coming from groups of at-risk couples, but instead from intrigue over the promise of genetic inquiry. The genome project is the central symbol of an expected revolution in genetic medicine, yet the benefit to health and well-being may come mostly from somatic cell therapy and advances in carrier and prenatal screening. The rationale for inviting new couples into the IVF arena for preimplantation diagnosis is not compelling.

New Field or Refined Technique?

Beyond the general questioning of goals is the need to fix responsibility for integrating embryo diagnosis into society. If, indeed, embryo diagnosis is the first step toward embryo therapy, something new is afoot - an emerging body of applied knowledge with an uncertain identity. Embryo genetics may be one of three things: an extension of IVF, a distinct field of medicine, or an extension of prenatal screening. The professional and institutional identity of preimplantation diagnosis is important to study because it will color the ethic under which the technique is applied in the clinical setting.

Is embryo diagnosis an extension of IVF? If so, primary oversight lies with obstetricians, infertility specialists, and reproductive endocrinologists. Medical doctors head the clinics, and couples work with nurse coordinators. The "patient" is the couple experiencing infertility or genetic risk. Diagnosis is aimed at helping the couple have a healthy baby. The doctor and patient are partners and the couple's autonomy is valued, but the physician's professional competence determines which embryos are transferred right away, which are frozen, which are not transferred. Judging an embryo's transferability is a technical decision related to the embryo's morphology and other physical traits. The goal is to maximize, under safe conditions, the odds for a successful pregnancy and to minimize risks and false hopes for the couples.

An advantage of seeing embryo diagnosis as an extension of IVF is that a voluntary apparatus is already in place to oversee it. The American Fertility Society (AFS) and its Society for Assisted Reproduction, for example, yearly gather and publish data from member IVF clinics.[9] The AFS makes available to couples a list of questions to ask upon entering an IVF program, its ethics committee has published minimum standards governing IVF and ethics reports, and IVF clinicians are now meeting occasionally to discuss methods and procedures for starting embryo diagnosis.[10]

A disadvantage is that if marketed as just another facet of IVF, the heralding of embryo diagnosis as something new is missing and with it the opportunity to question the reasons behind its introduction and its contributions to individual and societal well-being. Moreover, it opens embryo diagnosis to IVF couples as a matter of course, which contravenes the original intention of embryo diagnosis as being for at-risk couples.

Is embryo diagnosis a new field of medicine? Although still early for speculation, it appears the stage is being set for the image of the embryo as "patient." Micromanipulations already create the context for correcting deficiencies in embryos. One day the twinning of embryos may be offered as medical insurance for the embryo. If an embryo is twinned before biopsy, one part can be biopsied and discarded while the intact part is transferred. Or the biopsied half can be transferred and the intact half frozen in the event the embryo does not cleave or implant. In either case, the technique protects the embryo proper, thereby enhancing its status as a "patient."

Seeing the embryo as patient complements evolving notions of the fetus as patient. Both advance the idea that entities are subject to protection and care before birth. Efforts to save a potential child or "rescu[e] an ailing embryo"[11] direct attention to the embryo or fetus as the object of attention rather than to the couple. Regarding the embryo as patient has analytic benefits. It presents a context for studying new techniques and gives embryo diagnosis a separate identity as a distinct field with identifiable dilemmas and rich possibilities for ethical analysis based on graduated definitions of "patient."

On the other hand, regarding the embryo as patient runs the danger of personalizing the embryo and further confusing the question of the beginnings of life. It also sets the stage for elevating the embryo to the status of an entity with rights. This restricts experimental protocols and defines the embryo as ill or needy, which in turn creates a new set of medical "needs" for embryo therapy. Moreover, if the embryo is the patient, this arguably enhances the clinician's authority in making decisions. When the embryo is something to which things (tests, manipulations) are done, the practitioner's judgment becomes more important than ever, which further mutes the couple's nonexpert voice.

Is embryo diagnosis an extension of prenatal screening and genetic counseling? If so, the context is less distinctly medical and the personnel more likely to be scientists and social workers or psychologists. Clinicians' goals are to help couples make choices about whedier to conceive, provide information so couples understand the nature of their genetic risk, and set the stage for reproductive decisions. Genetic counselors use a model of nondirectionality and, at least in theory, maintain their impartiality. There is no real "patient," but instead a partnership between counselor and couple to allow a couple to make informed reproductive decisions based, among other things, on diagnostic tests. Genetic counseling allows couples to make choices, even though they may seem irrational.

If embryo diagnosis is an extension of prenatal screening, decisions will be made in a context where the couple's autonomy is valued. Genetic counselors, in general, guard individual choice. Thus, if a couple learns the fetus has an abnormality and asks the genetic counselor, "What would you do?" the counselor is inclined to defer the question and shift the conversation to the couple's needs and values.

One would expect a similar model to prevail if methods developed in relation to fetuses are used for embryos. Decisions regarding embryos will be presumed to be reproductive decisions, with autonomy paramount, rather than medical decisions, where expertise is a primary criterion. This protects the human interests in embryo diagnosis and acts as a brake to overeager expansion of embryo technologies. Each time a decision is to be made about what to do with embryos (whether and what to test, how to interpret results), the interests of the couple are built into the structure and the outcome is not predetermined. Critics have long claimed that new technologies depersonalize reproduction. The autonomy model of prenatal screening arguably helps protect against this.

On the other hand, maximizing individual choice is not an unrelieved blessing either. How far should individualism go? Should a couple in the future be able to select an embryo of the desired gender, say, and then twin it, freezing one twin for a later year to see the first child's personality and physical traits and then, if the child passes muster, have a genetically identical but younger twin?

A pure model of nondirectionality, with the presumption in favor of family choice, may not be desirable or even desired by couples in an era of increasing reproductive choices. What choices will people make if their array of options is not bounded? Will they find satisfaction from making these choices or might they instead be faced with unnecessary confusion and anxiety? Reproductive satisfaction is not necessarily achieved through more medical technology.

Ethics and Clinic Policies

Embryo diagnosis should take place in IVF clinics adhering to rigorous quality control in laboratories. The couples' autonomy should be respected, although the clinic teams bear the responsibility for setting borders on the range of decisions offered. Embryo diagnosis potentially creates a need for IVF among new groups of women, sets the stage for the spiraling development of new technologies (which is an elevator up or slippery slope down, depending on one's perspective), and creates new felt obligations for couples who might be happier conceiving through sexual intercourse and taking their chances on the usual outcome of having a healthy baby. Beneficence, then, might rest more in setting limits than expanding them. In placing limits, clinics are gatekeepers regulating the pace and substance of embryo manipulations. To be decided are matters of whom to invite into programs, what options to allow, what information to give, and to what extent team members should take societal interests into account in their informal policies.

Whom to admit? Assume a couple, at risk for having a child with the fatal condition of thalassemia, have experienced two terminations of affected fetuses and have two healthy children. Assume further that the husband wants a third child. The wife, who has medical problems and wants nothing more to do with prenatal screening, contacts the clinic about the possibility of embryo diagnosis. In asking whether the procedure is in the couple's best interest, one can understand their wariness over more prenatal screening. On the other hand, they have two healthy children, and the wife has been through prolonged emotional trauma. It may be that the couple is better off not knowing that the option of embryo diagnosis exists. Conservatism is warranted regarding whom to admit. One answer is to develop a criterion of "worthiness," measured in personal suffering and a legacy of loss, with the assumption that the "neediest" will be given the first opportunity to try this experimental protocol. The converse is to admit those with low emotional investment, inasmuch as the procedure is experimental and embryo loss is to be expected. This is a judgment call, but it should be articulated as part of the clinic's ethics.

What to offer? One clinic starts embryo diagnosis by testing embryos for sickle cell anemia. Another offers polar body biopsies for cystic fibrosis. A third offers sex-preselection for Duchenne muscular dystrophy. Two directions are possible. One is specialization, with individual centers specializing in a particular form of biopsy or a particular genetic disorder. Another is to focus on regional centers that offer several options. Strategy about expanding services ought to be developed deliberately as part of the clinic's policy. For example, a conservative course is to agree that new procedures will not be added until several healthy babies have been born from application of the core procedures. The expansion to different practice - different diseases, biopsy procedures, sex preselection - should be done gradually and with specified criteria in mind.

What should couples be told under conditions of uncertainty? The consent form at one clinic, for example, includes two general statements about the unforeseeability of risks to the patient, fetus, and child. The warning seems vague, but on the other hand, as Robert Veatch has noted, too much information can be "terribly tedious."[12] At some point the development of IVF, practitioners blew the whistle on exploitive practices and inadequate or inaccurate information about success rates. These same warnings can be repeated with embryo diagnosis, and the same standards of full disclosure need to be developed. The content of information packets and consent forms will stand the greatest chance of being readable and informative if clinics share their forms and if practitioners talk with one another to present information that can be modified according to a clinic's own success rates and new technical developments.

Under what overarching ethics should decisions about clinic policies be made? Some IVF practitioners are reluctant to take embryo diagnosis seriously, thinking variously that (1) with no federal funding for embryo research, diagnosis will not develop, (2) crises should not be anticipated and cannot be predicted, (3) IVF has worked smoothly with no significant safety problems so embryo diagnosis will follow suit, and (4) genetic diagnosis is "pie in the sky." This sets the stage for trial and error muddling as happened in the early days of IVF and embryo freezing, where consent forms were spare, success rates misleading, and clinic policies ad hoc. A clinic policy should be constrained by the ethics of individual practitioners on the one hand and societal views about what is and is not appropriate on the other. Embryo diagnosis is a rapidly changing technology being introduced quietly in the clinical setting. This technology will ultimately affect the genetic composition of future humans, and it creates a new specialty at a time when discrepancies in medical treatment between rich and poor are entrenched and growing. It brings the yearning to control the life course to a point so early in development that it negates the value of chance in every, day life.

Yet despite the importance of this field, there is a constitutional zone of protection around the technologies, the government is stymied about research involving embryos, and application is driven in no small measure by the promise of economic gain. Although patient advocacy groups can draw attention to the need for reforms, realistically the primary responsibility for framing coherent policies falls on the clinics that offer embryo diagnosis. These policies should be deliberate, crafted before the techniques of preimplantation diagnosis are applied in practice, and narrowly drawn regarding the options offered and patients accepted.

The ethics of individual clinicians should be articulated as a starting point for discussion within clinics with due humility about what is not known in genetics. Clinicians must bear the burden of showing the absence of harm to couples and potential children and the presence of clear benefit to specific groups of people. The ethics should protect the autonomy of couples who are not ill supplicants but healthy people making choices about reproduction. Efforts must be made to develop policies across clinics, communication should be open and free, and negative as well as positive results must be conveyed to clinicians and the public. Moreover, clear lines of responsibility should be developed within and across centers so that models of patient choice are clear, open to discussion, and consistent among team members.

Open, Critical Debate

The attitude of mind must come into play such that people rigorously ask and weigh questions about reasons for diagnosing human embryos, criteria for adding new genetic technologies in the future, distinctions between deeply felt needs and newly created ones, and the willingness to draw limits in the absence of legislation. Moreover, careful attention must be given to what, if anything, in embryo diagnosis and therapy is qualitatively different. One perspective holds that embryo diagnosis is not, in fact, distinctive: it merely pushes prenatal screening to an earlier stage and is just another step in IVF. A second perspective holds that embryo diagnosis is problematic because it will be used in embryo therapy (the long-debated genetic engineering).

A third perspective holds that embryo diagnostics are significant not so much because embryos or genetics are involved as because this opens a new set of labor-intensive technologies to the few in an era of scarce medical resources and growing respect for community as well as individual health concerns. Embryo diagnosis is indeed the ultimate in disease prevention, but it must be reconciled with other preventive measures designed to improve the health of the many.

The speculative wonderings of a generation are now faced with empirical realities. Embryo diagnosis on the eve of clinical application presents a challenge to reframe long-stated worries about genetic manipulation in ways consistent with the present medical reality. Pragmatic decisions must be made about who will be recruited as research subjects, how the protocol will be packaged, and what boundaries will define the choices developed and offered. Reflections on ethics need to take into account principles under which embryo diagnosis will be offered; the varying ethical frameworks used among practitioners, clinics, and professional associations; the identity of embryo diagnosis within medicine; the extent to which diagnosis furthers the goals envisioned for it; and the nature and importance of those goals themselves.

To return to the analogy of the Gold Museum, much of the new genetics is surrounded by dazzle and publicity, but embryo diagnosis is proceeding amid darkness and quiet. Our task is both to dim the glare and shed light on new applications. Reasoned policy governing medical innovations depends on open examination and reasoned understanding.


[1.] A variety of techniques may be employed in preimplantation diagnosis, including embryo analysis, trophectoderm biopsy, and polar body biopsy. For discussion, see Yury Verlinsky, Eugene Pergament, and Charles H. Strom, "The Preimplantation Genetic Diagnosis of Genetic Diseases," Journal of In Vitro Fertilization and Embryo Transfer 7, no. 1 (1990):1-5; A. Dokras et al., "Trophectoderm Biopsy in Human Blastocysts," Human Reproduction 5, no. 7 (1990): 821-25; Charles M. Strom et al., "DNA Analysis of Single Cells for Single Gene Diseases," Abstracts of the First International Symposium on Preimplantation Genetics, Chicago, 14-19 September 1990. [2.] D. K. Griffin et al., "Fluorescent In-Situ Hybridization to Interphase Nuclei of Human Preimplantation Embryos with X and Y Chromosome Specific Probes," Human Reproduction 6, no. 1 (1991):101-5; A. H. Handyside et al., "Biopsy of Human Preimplantation Embryos and Sexing by DNA Amplification," Lancet (18 February 1989): 347-49; Svetlana Milayeva et al., "Successful Preimplantation Diagnosis for Gender Determination," Abstracts of the First International Symposium on Preimplantation Genetics, Chicago, 14-19 September 1990. [3.] Illinois Masonic Medical Center in Chicago is offering polar body analysis for cystic fibrosis. Its team has attempted sex-preselection for X-linked genetic diseases. Several other clinics are planning to offer polar body or embryo biopsy in the near future. A healthy infant has been born in England following biopsy at the embryonic stage for cystic fibrosis (personal communication, Mark R. Hughes, MD). [4.] "Germ Cell Gene Panel," Science 253 (23 August 1991): 841. [5.] Verlinsky, Pergament, and Strom, "Preimplantation Genetic Diagnosis," p. 4. [6.] See A. L. Muggleton-Harris and I. Findlay, "In-Vitro Studies on |Spare' Human Preimplantation Embryos in Culture," Human Reproduction 6, no. 1 (1991): 85-92; Kate Hardy et al., "Human Implantation Development In Vitro Is Not Adversely Affected by Biopsy at the 8-Cell Stage," Human Production 5, no. 6 (1990): 708-14. In polar body biopsy and trophectoderm biopsies, the embryo is left intact, but with embryo biopsy one or two cells are removed, with an uncertain long-term effect on the developing embryo. For discussion, see D. A. Melton, "Pattern Formation During Animal Development," Science 252 (12 April 1991): 234-41; Joel M. Schindler, "Basic Developmental Genetics and Early Embryonic Development: What's All the Excitement About?" Journal of NIH Research 2, no. 9 (1990): 49-55. [7.] Daniel Callahan, What Kind of Life? The Limits of Medical Progress (New York: Touchstone, 1990), pp. 63-65. [8.] E. Pergament, "Preimplantation Diagnosis: A Patient Perspective." Paper presented at the 5th International Congress on Early Fetal Diagnosis, July 1990, Prague, Czechoslovakia. [9.] See, for example, Medical Research International, "In Vitro Fertilization-Embryo Transfer (IVF-ET) in the United States: 1989 Results from the IVF-ET Registry," Fertility and Sterility 55, no. 1 (1991): 14-23. [10.] "Questions to Ask about an IVF/GIFT Program," American Fertility Society, Birmingham, Ala.; American Fertility Society, "Revised Minimum Standards for In Vitro Fertilization, Gamete Intrafallopian Transfer, and Related Procedures," Fertility and Sterility 53, no. 2 (1990): 225-26; Ethics Committee, American Fertility Society, "Ethical Considerations of the New Reproductive Technologies," Supp. 2, Fertility and Sterility 53, no. 6 (1990). [11.] E. Joshua Rosenkranz, "Custom Kids and the Moral Duty to Genetically Engineer Our Children," High Technology Law Journal 2, no. 1 (1987):1-53. [12.] Robert M. Veatch, The Patient as Partner: A Theory of Human Experimentation (Bloomington: Indiana University Press, 1987).
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Title Annotation:Genetic Grammar: 'Health,' 'Illness,' and the Human Genome Project
Author:Bonnicksen, Andrea
Publication:The Hastings Center Report
Date:Jul 1, 1992
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