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Biomedical subjects

B S Wilfond

Publications and source records attributed to B S Wilfond.

17 recordsLinked to original sources
PubMed2000

Limitations of informed consent for in utero gene transfer research: implications for investigators and institutional review boards.

Only 10 years after the first human gene transfer protocols were approved for adults and children, researchers have begun to consider gene transfer on the fetus. While preliminary animal research is ongoing, the enthusiasm and pace of research in this area suggest that human protocols for in utero gene transfer research may be seriously considered in the foreseeable future. Federal guidelines for fetal research rely on minimizing risk and informed consent to protect the "rights and welfare" of both the fetus and pregnant woman. However, in utero gene transfer research poses special challenges to informed consent. This research represents an innovative approach for very ill subjects and takes place in the prenatal setting. These features may converge to undermine the expectant parents' comprehension of, and voluntariness for participation in, research. In this case, informed consent may not be able to bear the weight of adequately protecting the fetus from undue research risks. To compensate for this limitation, and using the regulations for pediatric research as a guide, a greater emphasis should be placed on the benefit/harm assessment rather than informed consent. Selecting diseases/patients where good alternative treatments exist may maximize informed consent, yet this may be a trade-off that exposes the fetus to greater relative risks. On the other hand, selecting diseases/patients without good alternative treatments to prolong life may convey an overestimation of the potential benefits of these interventions, and although care should be taken to strive to improve understanding of these limitations, misunderstanding may persist. However, selecting diseases/patients with no good alternatives might make serious risks more tolerable, and this should take precedence over informed consent. The limitations of informed consent brought into focus by the special features of in utero gene transfer research may be relevant to a broader range of innovative investigations.

Clinical Protocols↗
PubMed1998

Hereditary hemochromatosis: gene discovery and its implications for population-based screening.

OBJECTIVE: To evaluate the role of genetic testing in screening for hereditary hemochromatosis to help guide clinicians, policymakers, and researchers. PARTICIPANTS: An expert panel was convened on March 3, 1997, by the Centers for Disease Control and Prevention (CDC) and the National Human Genome Research Institute (NHGRI), with expertise in epidemiology, genetics, hepatology, iron overload disorders, molecular biology, public health, and the ethical, legal, and social implications surrounding the discovery and use of genetic information. EVIDENCE: The group reviewed evidence regarding the clinical presentation, natural history, and genetics of hemochromatosis, including current data on the candidate gene for hemochromatosis (HFE) and on the ethical and health policy implications of genetic testing for this disorder. CONSENSUS PROCESS: Consensus was achieved by group discussion confirmed by a voice vote. A draft of the consensus statement was prepared by a writing committee and subsequently reviewed and revised by all members of the expert group over a 1-year period. CONCLUSIONS: Genetic testing is not recommended at this time in population-based screening for hereditary hemochromatosis, due to uncertainties about prevalence and penetrance of HFE mutations and the optimal care of asymptomatic people carrying HFE mutations. In addition, use of a genetic screening test raises concerns regarding possible stigmatization and discrimination. Tests for HFE mutations may play a role in confirming the diagnosis of hereditary hemochromatosis in persons with elevated serum iron measures, but even this use is limited by uncertainty about genotype-phenotype correlations. To address these questions, the expert group accorded high priority to population-based research to define the prevalence of HFE mutations, age and sex-related penetrance of different HFE genotypes, interactions between HFE genotypes and environmental modifiers, and psychosocial outcomes of genetic screening for hemochromatosis.

Female↗
PubMed1998

Mixed messages: presentation of information in cystic fibrosis-screening pamphlets.

Written pamphlets are an important source of information for individuals deciding whether to undergo carrier testing for cystic fibrosis (CF). Adequate understanding of the condition and reproductive options following the diagnosis of a fetus with CF are critical to informed decision making. The information given about CF and reproductive options in 28 pamphlets about carrier testing, from commercial and noncommercial organizations in the United States and the United Kingdom, aimed at prenatal and other populations, was assessed. The amount of information provided about CF showed a range of 1-37 sentences (median 6.5), with most being relatively neutral and with a minority conveying a positive or a negative image. Positive sentences were less common in British, U.S. commercial, and prenatal pamphlets. Statements about life expectancy also varied considerably, both in the ages provided and in the degree of optimism conveyed. In addition, the pamphlets varied in the amount of information they provided about reproductive options following the diagnosis of a fetus with CF. Abortion was mentioned in just 15 pamphlets, more often in the United Kingdom than in the United States and more frequently in pamphlets from noncommercial than in those from commercial organizations. Wide variation in the descriptions of CF and the reproductive options presented raises concerns about the extent to which any one pamphlet may present balanced information. The choices about what information to include in educational materials need to be explicitly considered on the basis of the message intended to be sent.

Cystic Fibrosis↗
PubMed1998

Cystic fibrosis newborn screening: impact on reproductive behavior and implications for genetic counseling.

OBJECTIVE: To evaluate the impact of newborn screening for cystic fibrosis (CF) on the reproductive knowledge and behavior of CF families and to determine if heterozygote detection with the immunoreactive trypsinogen (IRT) method in conjunction with DNA analysis (IRT/DNA) influences knowledge and attitudes about reproduction in false-positive families. METHODS: The Wisconsin CF Neonatal Screening Project investigated 650 340 infants from 1985 to 1994 in a comprehensive randomized controlled trial to study both benefits and risks of newborn screening and to determine if early diagnosis would improve the prognosis of children with CF. Assessments of reproductive knowledge, attitudes, and behaviors of 135 families of children diagnosed as having CF in both the early treatment group and control groups were made 3 months after diagnosis using a questionnaire which was completed by 100 families. The same questionnaire was administered 1 year later to evaluate retention of information. It was completed by 71 families. A follow-up assessment tool was also administered in 1994 and responses obtained from 73 families. Knowledge, attitudes, and behavior among false-positive families were also assessed at the time of the sweat test in 206 families who experienced IRT screening and 109 families tested with the IRT/DNA method. Follow-up assessments were completed 1 year later in 106 IRT families and 63 IRT/DNA families. RESULTS: In families with a CF child, 95% initially understood that there was a 1 in 4 risk in subsequent pregnancies, and there was good retention of this information 1 year later. At the 1994 assessment, 52% of families had not yet conceived more children, but 74% of these already had children. In the couples in whom CF was diagnosed in the first child, 70% (95% confidence interval = 54% to 85%) conceived more children. There were 43 subsequent pregnancies in 31 families. Prenatal diagnosis was used by 26% of the families (8/31) for 21% of the pregnancies (9/43). There were 3 pregnancies with CF detected, all of which were carried to term. In the false-positive groups, >95% of families initially understood that their child definitely did not have CF. There was no difference between false-positive IRT and IRT/DNA groups, and the information was retained at 1 year. Follow-up assessment 1 year after negative sweat tests revealed that 7% of the IRT and 10% of the IRT/DNA families still thought about the results often or constantly. When asked whether the experience of screening affected feelings about having more children, an affirmative response was obtained in 4% of IRT families but in 17% of IRT/DNA families. One year later, more than half of the false-positive IRT/DNA families did not understand that they were at increased risk of having a child with CF. CONCLUSIONS: We conclude that CF neonatal screening does not have a significant impact on the reproductive behavior of most families and that prenatal diagnosis is not used by the majority of CF families. IRT/DNA testing experiences seem to affect attitudes about having more children, and some parents are confused about the implications of the results, even with genetic counseling. However, persistent concerns about the sweat test result are limited. Questions raised by this study confirm the need for more research regarding the process of genetic counseling and its impact on reproductive attitudes and behavior in the newborn screening setting.

Cystic Fibrosis↗
PubMed1997

Ethical issues in umbilical cord blood banking. Working Group on Ethical Issues in Umbilical Cord Blood Banking.

OBJECTIVE: Banking umbilical cord blood (UCB) to be used as a source of stem cells for transplantation is associated with a set of ethical issues. An examination of these issues is needed to inform public policy and to raise the awareness of prospective parents, clinicians, and investigators. PARTICIPANTS: Individuals with expertise in anthropology, blood banking, bone marrow transplantation, ethics, law, obstetrics, pediatrics, and the social sciences were invited to join the Working Group on Ethical Issues in Umbilical Cord Blood Banking. EVIDENCE: Members were assigned topics to present to the Working Group. Following independent reviews, background materials were sent to the Working Group. CONSENSUS PROCESS: Individual presentations of topics at a 2-day meeting were followed by extensive group discussions in which consensus emerged. A writing committee then drafted a document that was circulated to the entire Working Group. After 3 rounds of comments over several months, all but 1 member of the Working Group agreed with the presentation of our conclusions. CONCLUSIONS: (1) Umbilical cord blood technology is promising although it has several investigational aspects; (2) during this investigational phase, secure linkage should be maintained of stored UCB to the identity of the donor; (3) UCB banking for autologous use is associated with even greater uncertainty than banking for allogeneic use; (4) marketing practices for UCB banking in the private sector need close attention; (5) more data are needed to ensure that recruitment for banking and use of UCB are equitable; and (6) the process of obtaining informed consent for collection of UCB should begin before labor and delivery.

Biomedical Research↗
PubMed1997

Cancer genetic susceptibility testing: ethical and policy implications for future research and clinical practice. Cancer Genetic Studies Consortium, National Institutes of Health.

Authors examine the ethical and health policy implications in the Cancer Genetic Studies Consortium projects, which attempt to collect data on the clinical benefits and harms of cancer genetic testing. They suggest that more data are needed on the long-term physical and psychosocial effects of testing and that further examination is needed of the ethical issues raised by testing.

Adult↗
PubMed1994

Severe hemolytic anemia associated with vitamin E deficiency in infants with cystic fibrosis. Implications for neonatal screening.

Three infants are described with cystic fibrosis (CF) and malnutrition leading to severe anemia beginning as early as 6 weeks of age. Laboratory studies demonstrated high reticulocyte counts, negative Coombs' tests, abnormal peroxide hemolysis test results, and biochemical evidence of vitamin E deficiency. Oral administration of alpha-tocopherol resulted in rapid correction of the in vitro hemolysis and improvement of in vivo hematologic indices. Investigation of these patients supports the conclusion that the hemolytic anemia of infancy in CF is caused by vitamin E deficiency and should be treated promptly with 50 IU/day of vitamin E. Because two of the three patients were identified in a CF screening/surveillance program, we can estimate that the frequency of clinically significant anemia in CF infants is 4%. Our observations demonstrate a potential advantage of CF neonatal screening for individual patients susceptible to vitamin E-deficient hemolytic anemia and suggest that confirmatory follow-up diagnostic studies, such as sweat tests, should be performed by 4 to 6 weeks of age.

Anemia, Hemolytic↗
PubMed1993

Application of DNA analysis in a population-screening program for neonatal diagnosis of cystic fibrosis (CF): comparison of screening protocols.

We compare two protocols for newborn screening for cystic fibrosis (CF). The first uses the immunoreactive trypsinogen (IRT) assay with a cutoff of > or = 180 ng/ml and a sweat test to identify CF patients. The second uses the IRT assay with a 100 ng/ml cutoff in conjunction with direct analysis for the delta F508 CF transmembrane conductance regulator (CFTR) mutation in a two-tiered (i.e., IRT/DNA) protocol, followed by a sweat test. We screened 220,865 newborns from Wisconsin for CF, using the IRT protocol identifying 369 infants with an elevated IRT, of whom 46 were found to have CF. Another 7 CF patients were identified who had a false-negative IRT level. The CF incidence in the white population was 1 in 3,431 (carrier incidence of 1 in 30). The IRT protocol had a sensitivity of 87% and a positive predictive value of 12.5%. We subsequently used the IRT/DNA protocol to screen 21,258 infants. Of 518 infants with an IRT level > or = 100 ng/ml, 24 carried at least one copy of the delta F508 CFTR mutation, and 4 of these infants were found to have CF, yielding a positive predictive value for this protocol of 16.7%. Direct comparison of the positive predictive value of the two protocols is not valid, because of the different populations screened. However, had the IRT protocol been used on the IRT/DNA cohort, 50 infants, including the 4 with CF, would have received sweat tests, yielding a positive predictive value of 8%. Because of the small sample size, this positive predictive value is not significantly different from that obtained for the IRT/DNA test. However, from a practical point of view the IRT/DNA approach does decrease considerably the number of sweat tests that must be undertaken. The number of false positives for the IRT protocol (46 in 21,258) is increased significantly compared with that for the IRT/DNA approach (20 in 21,258; P < .001). The incidence of delta F508 carriers detected in cohorts with an elevated IRT level was increased compared with the incidence in the general population. The direct costs for the IRT/DNA approach (100 ng/ml) were $11,374 per CF patient detected, compared with $10,187 per CF patient detected for the IRT protocol. Therefore, we conclude that the IRT/DNA approach to CF newborn screening decreases the number of false-positive subjects contacted, without a significant increase in cost.

Analysis of Variance↗
PubMed1992

The introduction of cystic fibrosis carrier screening into clinical practice: policy considerations.

Routine prenatal testing for cystic fibrosis (CF) should be halted until the detection rate reaches 95 percent. Pilot studies are needed in order to evaluate the feasibility of meeting education, consent, and counseling requirements in order to facilitate informed reproductive decisions by clients and to minimize the potential for confusion, stigmatization, and discrimination. Primary care physicians may not be trained adequately to provide appropriate information, and prenatal visits may not be an ideal setting. The public's interest in carrier testing, prenatal testing, and pregnancy termination is uncertain because CF patients have an increasing median survival, variable disability, and normal intelligence. Even with a goal that limits testing for the purpose of informed reproductive decision making, the considerable cost of screening per case prevented must be considered before it becomes public policy. Until these issues have been clarified, the duty of primary care physicians is to inform patients of the test's availability and to refer interested patients to qualified genetic counselors rather than to provide the test themselves.

Attitude to Health↗
PubMed1991

Current issues in neonatal screening for cystic fibrosis and implications of the CF gene discovery.

Many questions remain regarding the efficacy, toxicity, and costs of CF neonatal screening. It would be premature, in our opinion, to implement mass population screening of newborns for CF until the benefits and risks have been fully defined, and an adequate and logistically feasible testing system developed and/or highly effective therapy for CF lung disease becomes available. In addition, the ethical issues described herein need to be resolved. This pertains not only to the CF patient but also the heterozygote carrier. These reservations notwithstanding, the discovery of the CF gene should have a favorable impact both directly and indirectly on neonatal screening for the disease. Mutation analysis coupled to IRT testing seems most attractive at this time, at least on a research basis, but primary molecular diagnostic procedures might supervene in the future, particularly if they are financially feasible.

Chromosome Mapping↗
PubMedDate not supplied

The cystic fibrosis gene: medical and social implications for heterozygote detection.

The primary goal of mass screening programs for cystic fibrosis carriers should be to allow people to make more informed reproductive decisions. However, previous experience with genetic screening programs, including those for phenylketonuria and sickle cell disease, have revealed complex problems including error, confusion, and stigmatization. These problems could be greater with cystic fibrosis, since more than 8 million Americans may be carriers and entrepreneurial interests can be expected to promote screening in what could become a billion-dollar industry. The present frequency of the detectable mutation (delta F508), 75%, will complicate the counseling process. The sensitivity of the test to detect at-risk couples would be 56%. The cost of screening could be as much as $2.2 million for each cystic fibrosis birth avoided. Regardless of improvements in the detection rate, implementation of population screening should be delayed until pilot studies that demonstrate its safety and effectiveness are completed. While studies are in progress, preconception testing should be offered to adult relatives of cystic fibrosis patients as part of a comprehensive program following institutional review board approval for "compassionate use." The purpose of such review should be to ensure that strict standards of informed consent, education, quality control of the testing procedure, and counseling are followed. Primary care physicians who are unable to offer screening as part of such a comprehensive program should refer high-risk patients who would like to consider being tested to established centers.

Cystic Fibrosis↗
PubMedDate not supplied

National policy development for the clinical application of genetic diagnostic technologies. Lessons from cystic fibrosis.

In recognition of the earlier experiences with genetic diagnostic services and in anticipation of a greater potential for genetic testing for presymptomatic disease and disease susceptibility, this article provides an analysis of policy development for cystic fibrosis carrier screening. The deficiencies of relying on an extemporaneous model for health policy development are described. Preferably, an evidentiary model, based on the evaluation of clinical research and incorporating professional and public attention to underlying normative issues, should define the standard of care. Appropriate procedural mechanisms should be established at both state and federal levels to prevent the unnecessary confusion, expense, and personal or social harms likely to result from a completely unrestrained application of developing genetic technologies or continuing ad hoc responses to rapid increases in genetic diagnostic capabilities. A broadly constituted national advisory commission on the ethical, legal, and social implications of the Human Genome Project would provide an important locus for national decision making and may offer an efficient mechanism for implementing the evidentiary model, promoting public involvement at a time when social policy decisions must be made to restructure the health care system to be more sensitive to issues of access, allocation, and costs.

Advisory Committees↗