Counselling for prenatal diagnosis of sickle cell disease and beta thalassaemia major: a four year experience

Making the 'genetic counsellor' in the UK, 1980-1995

The professional identity of the 'genetic counsellor' first took shape in the UK in the early 1990s, when the University of Manchester established the country's first masters-level training course. Postwar, genetic counselling had been carried out by (male) clinical geneticists, who, alongside their research, clinical and field-building activities, met patients and families to discuss inherited conditions and risk estimates, and who sometimes advised parents whether to attempt or continue pregnancies. By contrast, the new cohort of students in Manchester in the 1990s were not medically trained, were mostly women, and were schooled in the psychological and social consequences of genetic testing and diagnosis, as well as methods for the care, support and emotional management of patients and families. This was a significant change both in the practices of 'genetic counselling' and who was expected to practise it. Focusing on a small section of this history, between 1980 and 1995, this paper describes some of the historical threads that contributed to this change. It charts the early work of genetic nurses and social workers, who in the 1980s carved out distinctive roles within National Health Service genetics centres. It describes the separate, specialist provision developed by sickle cell and thalassaemia counsellors, who developed new approaches in dialogue with racialised and underserved patient communities. It examines growing interest in the late 1980s and early 1990s in the tacit social and cultural conditions of genetic counselling encounters, and how this cohered with attention from disability scholars, psychologists and social scientists. By describing these historical contributions, this paper explores how the intersecting gendered, racialised and disciplinary politics of clinical genetics shaped the new professional role of the 'genetic counsellor'.

Prenatal diagnosis of sickle cell disease by the technique of PCR

Sickle cell disease (SCD) is prevalent in Central India and causes major morbidity and mortality. There is a lack of prenatal diagnostic facility near population affected with SCD. This is the pilot study in our region with the aim to establish prenatal diagnostic facility for the couples carrying sickle cell gene in Central India, in order to help them take an informed decision regarding fetus affected with SCD and also to calculate sensitivity of polymerase chain reaction (PCR) technique in our set up with follow up high performance liquid chromatography (HPLC) of baby's blood sample. Fetal sampling was done by chorionic villous biopsy. Extracted DNA was subjected to amplification refractory mutation system (ARMS-PCR) to detect sickle cell mutation (GAG → GTG) in the sixth codon of β globin gene. Follow-up HPLC was done to detect baby's Hb pattern. Prenatal diagnosis of sickle cell anemia was offered in total 37 cases out of which one (2.7 %) fetal sample was inadequate. Total 26 (70.27 %) fetuses had AS Hb genotype, 3 (8.11 %) had AA Hb genotype and 3 (8.11 %) had SS Hb genotype while remaining 4 (10.81 %) were given AA/AS Hb genotype. All couples with SS fetuses opted for MTP. Follow up HPLC was performed in 24 cases, out of which 18 (75 %) were correlated and 6 (25 %) were mismatched. In present study sensitivity of ARMS-PCR was 75 %. ARMS-PCR is a simple technique to be established initially for providing rapid prenatal diagnosis to the couples with known sickle cell mutation. The sensitivity of ARMS-PCR can be increased by using suitable techniques to detect maternal cell DNA contamination.

BRCA carriers' thoughts on risk management in relation to preimplantation genetic diagnosis and childbearing: when too many choices are just as difficult as none

Women with a BRCA mutation have unique concerns about childbearing and future fertility. In a focus group conducted among unaffected carriers, the majority of women held positive attitudes toward preimplantation genetic diagnosis to reduce transmission to future offspring and further identified unmet needs for education and support for decision making.

Preimplantation genetic diagnosis for the prevention of sickle cell disease: current trends and barriers to uptake in a London teaching hospital

INTRODUCTION

Sickle cell disease (SCD) is a clinically significant hemoglobinopathy with increasing global incidence. We describe our experience of using pre-implantation genetic diagnosis (PGD) for the prevention of SCD at a tertiary referral centre in London.

METHODS

Between January 2002 and December 2007, of 78 at-risk couples referred for PGD treatment, 12 couples (15%) underwent 16 PGD cycles for the prevention of SCD. RESULTS. The live birth rate was 13% per initiated cycle, 18% per embryo transfer and 17% per couple.

CONCLUSIONS

Although PGD for prevention of the birth of a child affected by SCD is a viable treatment option for couples at risk of having an affected child, potential barriers to uptake of this service need to be fully addressed to ensure its availability to all couples seeking to avoid having a child affected with SCD.

The UK control programme for the haemoglobin disorders

The haemoglobin disorders are a group of recessively inherited conditions of varying severity. In the homozygous state, alpha zero thalassaemia causes hydrops fetalis, beta thalassaemia usually causes a severe transfusion-dependent anaemia and sickle cell anaemia (HbSS), haemoglobin S/C disease, haemoglobin S/D disease and haemoglobin S/beta thalassaemia cause sickling disorders ranging from quite mild to very severe. Haemoglobin disorders are among the commonest inherited diseases in the UK. Management can be very burdensome, but produces good results in many cases. The disorders can also be prevented by a programme of carrier screening, genetic counselling and prenatal diagnosis in populations at risk. The WHO has defined a “haemoglobinopathy control programme” as an integral strategy combining optimal patient care with prevention based on community education, propective carrier diagnosis, genetic counselling and the offer of prenatal diagnosis. The services required for haemoglobin disorders in the UK have recently been reviewed in a report from the Standing Medical Advisory Committee of the Department of Health. This report focuses on genetic counselling and prenatal diagnosis for haemoglobin disorders.

Reproductive decisions of parents of children with metabolic disorders

The Interaction Model of Client Health Behavior (IMCHB) served as a guide for variable selection and instrument development for telephone interviews with 230 parents of children with metabolic disorders. Sociodemographic, psycho-affective and client-professional interaction variables were examined in relation to three outcomes: (1) receptivity to future prenatal diagnosis (56% were receptive); (2) likelihood of terminating an affected pregnancy (10% would); and (3) whether or not the parent had taken measures to prevent another affected pregnancy (41% had). All three outcomes were significantly correlated with higher scores on the Parent Stress Index, lower scores on the Vineland Adaptive Behavior Scales, fewer persons in the parent's social support network, greater worry about the living child's future and greater perceived difficulty meeting the child's extra care needs. A regression model constructed to explain taking measures to prevent a future affected pregnancy illustrated the usefulness of the IMCHB in research that involves multiple interacting variables on health outcomes. Few of the parents (7.4%) reported an interaction with a genetic counsellor, highlighting the need for practitioners from multiple disciplines to be adequately educated in principles of genetics, especially the psychological and affective aspects of counselling.

Long-term effect of prospective detection of high genetic risk on couples' reproductive life: data for thalassaemia

Prospective risk detection with availability of prenatal diagnosis is the best service currently available for couples at high genetic risk Here we describe the long term effect of this service on the reproductive life of 102 couples at risk of thalassaemia, whose risk was detected prospectively by carrier screening, who made use of prenatal diagnosis, and where the woman is now over 40. Overall outcome for couples is described in terms of number of favourable versus unfavourable pregnancy outcomes. (A favourable pregnancy outcome = unaffected livebirth, or affected livebirth resulting from informed parental choice.) The 102 couples had a total of 356 pregnancies, including 302 viable pregnancies, and 88% achieved a family unburdened by thalassaemia. 68% of viable pregnancies had a favourable outcome, but only 43% of couples had only favourable outcomes, and 26% lost two or more viable wanted pregnancies. When early losses are included 58% of pregnancies had a favourable outcome, but only 30% of couples had only favourable outcomes, and 41% lost two or more pregnancies. Even with the best available service, at risk couples remain victims of chance, and a significant minority experience great difficulty in obtaining even one healthy child. Research is needed on approaches that may allow couples better control of reproductive outcomes.

"Race", ethnicity and haemoglobin disorders

The new genetics has brought forth concerns that such developments as screening for genetic diseases will accentuate the oppression of minority ethnic groups [Bradby (1996) Genetics and racism. In The Troubled Helix: social and psychological aspects of the new human genetics, ed. T. Marteau and M. Richards, pp. 295-316. Cambridge University Press, Cambridge]. Haemoglobin disorders primarily affect minority ethnic groups in the U.K. but have been the subject of protest regarding lack of services as much as the unwelcome advent of them. This paper examines various conceptions of "race", from biological reductionism, through notions of ethnicity, racialized groups, sociological conceptions of "race", political and analytical uses of the term "Black" and so-called "new ethnicities" such as situational and plastic ethnicity in order to examine the consequences of these competing conceptions of race for a social analysis of sickle cell anaemia and beta-thalassaemia. The paper concludes that any group of people associated with the haemoglobin disorders are subject both to constraints upon their actions and opportunities for re-interpreting their social world. In conclusion it is proposed that no nomenclature classifies the phenomenon unproblematically. The notion of race as a political construct [Goldberg (1993) Racist Culture: Philosophy and the Politics of Meaning. Blackwell, Oxford] is used to suggest that attempts to construct all-embracing definitions themselves signal the potential abuses which may be attendant upon programmatic or mechanistic conceptions of the relationship between race and haemoglobin disorders.

Global epidemiology of hemoglobin disorders

Thalassemias and the hemoglobinopathies such as Hemoglobins S, C and E, are now a global problem. They have spread through migration from their native areas in the Mediterranean, Africa and Asia and are now endemic throughout Europe, the Americas and Australia. Comprehensive control programs in recent years have succeeded in limiting the numbers of new births and prolonging life in affected individuals. Such programs have been successful in a minority of countries and have little global impact. Over 300,000 infants with major syndromes are born every year and the majority die undiagnosed, untreated or under-treated. Countries may be divided into three general categories according to the services available: A. Endemic Mediterranean countries. In these long-established prevention programs have succeeded in achieving 80%-100% prevention. Specialized clinics able to provide optimum treatment. B. Areas of the developed, industrialized world where prevalence is increasing because of migration. These countries have the means to provide adequate control but have problems in reaching immigrant groups with different cultural background. C. Countries of the developing world where the provision of services is hampered by economic difficulties, other health priorities due to high infant mortality from infectious diseases, and religious/cultural constraints.

Prenatal screening for haemoglobin disorders

The technology has been available to detect carriers of haemoglobin disorders since the late 1960s. Prenatal diagnosis has been available since 1978. First trimester diagnosis by chorionic villus sampling and DNA analysis was introduced in 1982, and subsequent simplifications in DNA technology have made screening, counselling and prenatal diagnosis cost-effective at the community level, in countries at all levels of development. Audit of prenatal diagnosis for haemoglobin disorders in countries which have the resources and infrastructure necessary for genetic population screening (such as the UK and other European countries), has shown that the number of prenatal diagnoses actually performed fall far short of expectation. The demonstration that this reflects failures in delivering information, screening and counselling to the populations at risk, rather than rejection of prenatal diagnosis, shows the importance of placing more emphasis on the organisational and social requirements for genetic population screening. In some countries current attitudes towards abortion exclude provision of prenatal diagnosis within the health service, but in many such cases it has been set up in the private sector. It is also being introduced through combined private and charitable efforts in an increasing number of developing countries, including some with extremely limited health resources: such centres are likely to act as nuclei for emergence of genetics services in these communities. A particularly notable recent achievement is the introduction of prenatal diagnosis in Nigeria, where 1-2% of all children born suffer from sickling disorders.

Contraceptives, counselling, and pregnancy in women with sickle cell disease

Sickle cell disease is listed in the manufacturers' data sheets in the United Kingdom as a contraindication to the use of most combined contraceptive pills; the result is confused advice on family planning to a group of women who are at substantial risk from both planned and unplanned pregnancy. A study in north London on the use of contraceptives by women with sickle cell disease indicates that the use of combined oral contraceptives is common. Although medical staff usually advised against pregnancy, such advice was almost always ignored. Over half of the women surveyed had some knowledge about antenatal diagnosis. Family planning advice should be an integral part of the care of women with sickle cell disease. In the absence of specific data to the contrary all methods of contraception may be considered, although with appropriate caution.

Ethical aspects of genetic screening

Public and professional concern associated with the idea of genetic screening has generated numerous publications on the ethics of genetic screening (e.g. 1-4). Concerns revolve around inadequate consultation before screening is carried out, the unearthing of worrying risks, the use of genetic information in ways that could be disadvantageous to the person involved, stigma, and a phenomenon known as the 'technological imperative', which means that simply because a technology is available there is a tendency to use it. Most reports agree that, in practice, the main ethical problems are likely to involve screening for risk of common diseases of adult life, because of the possible impact on a person's healthy self-image, implications for health and life insurance, and the possibility of commercial exploitation of people who know themselves to be vulnerable. In this paper I do not propose to address these issues directly. I have been invited to discuss this subject as a clinician involved with genetic screening, counselling and prenatal diagnosis for the haemoglobin disorders, the most common serious human recessively inherited diseases. Since we are scientists, any recommendations we make should be based on experience: my aim is to show that experience is often surprising, and that it is often possible to meet public concerns by taking quite simple practical steps.

Factors affecting the uptake of prenatal diagnosis for sickle cell disease

Between 1979 and 1990, 170 couples at risk of having children with sickle cell disease, resident in the UK and with a continuing pregnancy, were referred for counselling at the University College Hospital Perinatal Centre. Approximately 50% of the couples, including those where one partner actually had sickle cell disease, requested prenatal diagnosis. This was requested in 82% of pregnancies when the mother was seen in the first trimester of pregnancy and in 49% when she was seen in the second trimester. More than 90% of referred couples who already had an affected child requested prenatal diagnosis. The type of sickle cell disease involved and ethnic group also influenced choice. These results show the importance of detecting and counselling couples at risk before pregnancy whenever possible.

Research studies in applied human genetics: a quantitative analysis and critical review of recent literature

To determine the extent to which speculations about the social, legal, and ethical implications of genetic counseling, screening, and prenatal diagnosis are being studied empirically, the substantive contents of major genetics (N = 5) and obstetrics journals (N = 2) from the years 1985-1989 were reviewed. Among the approximately 9,000 articles published, only 58 containing relevant substantive data could be identified. Data collected in a single study were reported in more than one article in at least ten cases so that these articles actually represent only 45 distinct studies. Most described investigations of the attitudes and reactions of individuals or couples who had had or been referred for genetic counseling or prenatal diagnosis. These observational studies generally employed study-specific questionnaires, many of which were apparently self-administered by respondents, to obtain data. This survey and analysis of the recent literature suggests that despite frequent editorials and other commentaries underlining the problematic nature of developments in medical genetics and calling for their investigation, the "gate-keepers" to this service continue to pay scant attention to these issues in their reported research. Innovative and interdisciplinary studies that will provide information to close the many gaps in our understanding of the consequences of developments in applied human genetics are recommended for the future.

Prenatal screening for hemoglobinopathies. III. Applicability of the health belief model

A comprehensive prenatal hemoglobinopathy screening program in Rochester, NY, has been described in a preceding paper in this issue of the Journal. A woman identified as a carrier may face three decisions. The first is whether to accept the offer of counseling. The second is whether to have her partner tested. If her partner also tests positive, then the third decision is whether to accept the offer of prenatal diagnosis. This report analyzes factors affecting her decision, with special attention being given to factors invoked by the Health Belief Model. Factors predicting that a patient who we identified as a carrier would come for counseling included the following: patient had no prior knowledge that she is a carrier (P less than .001), a gestational age less than 18 wk (P less than .01), and Caucasian race (P less than .05). For sickle cell trait counselees and beta-thalassamia trait counselees, factors found to predict patient's intent to have partner tested were the following: a greater postcounseling knowledge of the disease (P less than .009), a lesser perceived burden of intervention (P less than .011), and belief that the partner is also a carrier (P less than .008). Also for sickle cell trait counselees and beta-thalassemia trait counselees, factors predicting that the partner actually will be tested were the following: living with the partner (P less than .001), gestational age at identification less than or equal to 18 wk (P less than .001), a lesser perceived burden of intervention (P less than .002), and a greater perceived seriousness of the disease (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

The presentation, management and prophylaxis of sickle cell disease

Sickle cell disease (SCD) is encountered in all parts of the world where plasmodium falciparum has been endemic and has spread by migration to the temperate countries of the world resulting in a heavy caseload in Northern Europe and the United States. These patients in the temperate climates manifest most of the clinical problems associated with SCD in Tropical Africa and the West Indies. There are, however, differences between the groups in both the frequency and presentations of the clinical syndromes. The clinical management of SCD is discussed with particular reference to the potentially fatal sequestration syndromes: splenic, hepatic, 'the girdle syndrome' and 'the chest syndrome'. In all clinical situations encountered in SCD blood transfusions should be by isovolaemic exchange unless there is a marked fall in haematocrit (less than 5 g/dl) as may occur with sequestration and aplasia. The criteria for exchange transfusion in the chest syndrome are a pAO2 of less than 60 mm Hg while breathing air or a rapidly deteriorating clinical picture. Analgesia for vaso-occlusive sickle pain should be adequate and freely available which often requires the parental administration of opiates. We have delineated a small sub-group (6%) of SCD patients, 'the non-copers', who manifest a high demand for analgesia. The prospects for cure, and the techniques and issues for antenatal diagnosis are reviewed demonstrating the importance of education and counselling. The significant reduction in mortality and morbidity of children with SCD taking penicillin prophylaxis is emphasised with the need for its early institution.