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In "The Ethical Justification for Minimal Paternalism in the Use of the Predictive Test for Huntington's Disease," David DeGrazia attempts to provide a rational analysis of the exclusion criteria and counseling requirements for predictive testing proposed by the Huntington's Disease Society of America (HDSA). The need for analysis is clear. These protocols and procedures for predictive testing for Huntington's disease (HD) are being used as models for testing programs for any number of genetic conditions. DeGrazia concludes that the HDSA guidelines are reasonable, a conclusion with which I agree. However, I believe that DeGrazia, by placing his analysis within the framework of autonomy versus paternalism, overlooks both the fundamental rationale for the testing procedures and the true barriers to testing.... The difficulties encountered during the testing process clearly demonstrated the failure of abstract principles to deal with real life.
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...I shall summarize my argument to this point. 1) A new technology -- medicalizing life choices -- introduces additional sources of uncertainty into the physician-patient relationship. The implications for the authority-autonomy tension of that relationship are not fully worked out, as is evidenced by differing views on professional obligations. 2) The warrants for paternalism are complex, ranging from a pragmatic response in the face of uncertainty to a proactive, highly directive determination of the patient's best interests. 3) Although some proponents of autonomy argue that it entails positive rights to intervention and information, the "strong sense" of autonomy is not the prevailing view. 4) The as yet unclear benefits of knowledge about one's genetic makeup are even less clear in the case of HD. Strong circumstantial evidence of risks of harm from disclosure of unfavorable test results have not been dispelled by early experience with use of the HD test. 5) A cautious approach in the use of HD test seems warranted, even at the cost of restricting autonomy. Legitimating that approach by reference to traditional ethical theory is a necessary element in the transfer of the new technology to the wider clinical setting. 6) While PMP [the principle of minimal paternalism] attempts to offer such an approach, some questions do not appear to have been resolved or fully addressed by this formulation.
Adolescents who are actively requesting Huntington's predictive testing of their own accord pose a dilemma to those providing testing. In the absence of empirical evidence as regards the impact of genetic testing on minors, current policy and guidelines, based on the ethical principles of non-maleficence and respect for individual autonomy and confidentiality, generally exclude the testing of minors. It is argued that adherence to an age based exclusion criterion in Huntington's disease predictive testing protocols is out of step with trends in UK case law concerning minors' consent to medical treatment. Furthermore, contributions from developmental psychology and research into adolescents' decision making competence suggest that adolescents can make informed choices about their health and personal lives. Criteria for developing an assessment approach to such requests are put forward and the implications of a case by case evaluation of competence to consent in terms of clinicians' tolerance for uncertainty are discussed.
OBJECTIVE: At present, the problems associated with suicidal ideation and suicide in Huntington's disease (HD), worldwide, are much the same as 2 decades ago. This study seeks to investigate the psychological complications of predictive testing in HD at risk populations. METHODS: The key problems of predictive testing, fear of acquiring carrier status, psychological consequences, autonomy, and rights to know are discussed. RESULTS: This review (1) describes psychological affect and problems of persons facing the decision to test for HD, (2) discusses suicidal ideation, behaviour, and catastrophic events associated with predictive testing, (3) assesses ethical questions raised in the genetic counselling, (4) questions whether counsellors should promote or advocate predictive testing, and finally (5) discusses what professionalism actually is in genetic counselling. CONCLUSION: The need for professional counselling, using a well designed protocol, and the importance of focusing on the suicide risk of participants in predictive testing programs are emphasized. PRACTICE IMPLICATIONS: The counsellor has an obligation to provide adequate information. The professionals should not promote nor advocate presymptomatic DNA-testing. Depression, hopelessness, anxiety, emotional distress, suicidal tendencies, and social dysfunction grading should be considered in predictive testing of HD.
The identification of a DNA restriction fragment length polymorphism closely linked to Huntington's disease on the short arm of chromosome 4 has for the first time allowed presymptomatic prediction to be undertaken in first-degree relatives at risk. The late and variable onset of this dominantly inherited disorder makes such prediction a powerful and potentially valuable aid in genetic counselling, but in the absence of effective therapy there are serious ethical reservations concerning such a predictive test. The new developments have stimulated an active and informative debate among professionals and family members on whether and how predictive tests should be used. Guidelines have emerged which should be useful not only for Huntington's disease, but for other serious late-onset neurogenetic disorders. Meanwhile, studies in Wales and elsewhere have not only confirmed the original linkage but have excluded multi-locus heterogeneity as a significant problem. Genetic prediction for the individual at risk remains critically dependent on a suitable family structure, present in only a minority of families in Wales. A more feasible alternative for most families is prenatal exclusion, which can allow risk prediction for a pregnancy without altering the situation for the person at risk. This approach has already been applied in Wales; the experience gained will be useful in full prediction, which is currently being introduced.
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We have performed 31 exclusion tests (43 per cent) and 41 direct tests (57 per cent) in 43 couples at risk, in the period 1987 to 1997 in Leiden, The Netherlands. This resulted in termination of 28 pregnancies (39 per cent), with an increased risk. In 28 couples (65 per cent), the woman was at risk. Prenatal testing in consecutive pregnancies (mean number: 3) was performed in 15 couples (35 per cent), with a mean time interval of 15 months. Parents should make an independent choice for (every) pregnancy, although most (86 per cent) did not change their initial choice. It is important that the position of children in the same family, of whom some know their status as a result of prenatal testing, whereas others remain at risk, is taken into consideration in counselling. The relative number of exclusion tests when compared with direct tests has diminished since the mutation was identified. The prenatal exclusion-definitive test (Fig. 1) was rarely used (2/72, 3 per cent). Nowadays, direct mutation testing of the fetus only is simpler and faster and the risk of disclosure of the genetic status of the at-risk parent is only 25 per cent. This test should therefore be offered as another option and included in the international guidelines. The uptake for prenatal testing is low: for 2 per cent of the at-risk persons, 11 per cent of the tested carriers and a small group of at-risk persons wishing not to be tested themselves, prenatal testing seems an acceptable choice regarding reproduction.
International guidelines developed to minimize harm from predictive testing for adult-onset, nontreatable neurogenetic conditions such as Huntington disease (HD) state that such testing should not be available to minors. Some authors have proposed that predictive testing for these conditions should be available to minors at the request of parents and/or of younger adolescents themselves. They highlight the lack of empirical evidence that predictive testing of minors causes harm and suggest that refusing to test minors may be detrimental. The current study focuses on the context of predictive test requests by adolescents younger than 18 years, and presents arguments and evidence that the risk of potential harm from testing such young people is sufficiently high to justify continued caution in this area. A study based on a model of psychosocial maturity found that the 3 factors involved in maturity of judgement in decision making - responsibility, temperance and perspective - continue to develop into late adolescence. There is also evidence that the prefrontal areas of the brain, which are involved in executive functions such as decision making, are not fully developed until early adulthood. Combined with evidence of adverse long-term effects, from research with adults who have undergone predictive testing, these findings constitute grounds for retaining a minimum age of 18 years for predictive testing for nontreatable conditions. Further research on assessment of maturity will assist with reaching a consensus on this issue.
The recent identification of gene mutations involved in hereditary cancers increasingly allows for predictive DNA-testing. There is an urgent need to analyse the ethical issues involved. This article concentrates on the ethics of predictive testing for mutations in the breast (and ovarian) cancer genes BRCA1 and -2. Using international guidelines for presymptomatic DNA-testing for Huntington disease and the Li-Fraumeni syndrome as a model, a provisional protocol, which entails four parts is presented: (i) inclusion and exclusion criteria; (ii) preparing for the test; (iii) informing about the results of the test; (iv) post-test counselling and evaluation. The importance of an integral education of both doctors and the public is stressed.
PURPOSE: Predictive genetic testing is offered to asymptomatic adults even when there is no effective prophylaxis or treatment. Testing of young people in similar circumstances is controversial, and guidelines recommend against it. We sought to document descriptive examples of the occurrence of genetic testing in young people for nonmedical reasons, in the countries where guidelines exist. METHODS: Clinical geneticists in the USA, Canada, UK, Australia, and New Zealand were surveyed about the occurrence and outcomes of testing in asymptomatic young people for conditions where no prophylaxis or treatment exists and onset is usually in adulthood. RESULTS: Of 301 responses, details were provided of 49 cases where such testing had occurred. The most common condition tested for was Huntington Disease. In 22 cases (45%), the young person tested was immature, defined as under the age of 14 years. Results were disclosed to only two immature minors and in three cases parents experienced clinically significant anxiety related to how they would pass on information to their gene positive child. In 27 cases (55%), the young person tested was mature. Results were disclosed to 26 mature minors and it was reported that two individuals experienced an adverse event. Consistent follow-up did not take place and findings represent the minimum frequency of adverse events. The majority of respondents agree with existing guidelines but many believe each case must be considered individually. CONCLUSION: Clinicians agree with existing guidelines regarding predictive testing in young people, but choose to provide tests for nonmedical reasons in specific cases.
Fifty-five individuals at 50% risk of inheriting Huntington disease (HD) were given in-depth structured interviews to survey attitudes toward use of a predictive test and to assess the possible impact of such a test on the number of gene carriers born. Three-quarters of the sample said they would take predictive test. Given a positive predictive or prenatal test, the number of individuals choosing to have children is reduced from 80% of the total sample to 42%, or by almost one-half. The large proportion of at risk individuals who say they would use a predictive test underscores the importance of developing guidelines for its administration prior to implementation.
The discovery of DNA markers linked to the gene causing Huntington disease (HD) has allowed the development of predictive testing programs for persons at-risk. A pilot program was established in British Columbia in November 1986. Ninety-five persons are currently enrolled. The major objective of this project is to introduce and evaluate a protocol for the delivery of test results to persons at-risk for HD. The criteria for entry and details of the psychosocial assessment before and after receiving a modified risk are presented. The guidelines that are developed from this project will have major applications for predictive testing programs for other late onset autosomal dominant disorders.
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This study summarizes 10-years' experience of predictive and pre-natal testing and pre-implantation genetic diagnosis (PGD) for Huntington disease (HD) in Australia. Results are presented from 2036 direct mutation predictive tests conducted between January 1994 and December 2003. Thirty-eight per cent of results (776/2036) were positive, 56% (1140/2036) were negative, and 6% (120/2036)) were in the mutable normal (27-35 CAG repeats) or in the reduced penetrance (36-39 CAG repeats) ranges. Ninety-four per cent (1908/2036) and 6% (128/2036) of those tested had prior genetic risks of 50% and 25%, respectively. Twenty-seven per cent (34/128) of those at 25% risk had their genetic status changed to positive, thus revealing the positive status of their at-risk parent. During this period, 63 pre-natal tests were also conducted, and 13 children were born following PGD for HD. Social workers specializing in predictive testing counselling over this 10-year period across Australia identified and summarized particularly challenging counselling issues. These included the interpretation of mutable normal and reduced penetrance range test results, potential conflicts of interest between family members regarding testing decisions, unanticipated consequences of both predictive and pre-natal testing decisions, the importance of following protocols for predictive testing to facilitate long-term adjustment to results, and the potential for genetic discrimination. The identified issues highlight the importance of the protocols for predictive testing and indicate that extension of the international guidelines published in 1994 may be timely.
Huntington's disease (HD) and dominant ataxias (SCA) represent neurodegenerative hereditary diseases dominantly transmitted for which a direct and accurate genetic test is now available for molecular confirmation and presymptomatic test. Predictive testing programs, according to published international guidelines, are available worldwide. A large number of subjects (n=165) required a predictive HD diagnosis, although only 36% completed the program flow-chart and received the final genetic result (26 had a positive, 34 negative result for mutation). In 4 cases, an allele of intermediate range (33-34 CAGs) was found. Two of these shared the intermediate allele with an expanded repeat. In this case, we estimated the patient's risk to have affected children over the usually reported 50%. In 4 cases, the presymptomatic diagnosis was requested by persons at-risk for SCA1 and SCA3/Machado-Joseph disease. There were no adverse events to results of both HD and SCA presymptomatic diagnoses.