Antenatal diagnosis. How to deliver a comprehensive service in the United Kingdom

EMQN Best Practice Guidelines for molecular and haematology methods for carrier identification and prenatal diagnosis of the haemoglobinopathies

Haemoglobinopathies constitute the commonest recessive monogenic disorders worldwide, and the treatment of affected individuals presents a substantial global disease burden. Carrier identification and prenatal diagnosis represent valuable procedures that identify couples at risk for having affected children, so that they can be offered options to have healthy offspring. Molecular diagnosis facilitates prenatal diagnosis and definitive diagnosis of carriers and patients (especially ‘atypical' cases who often have complex genotype interactions). However, the haemoglobin disorders are unique among all genetic diseases in that identification of carriers is preferable by haematological (biochemical) tests rather than DNA analysis. These Best Practice guidelines offer an overview of recommended strategies and methods for carrier identification and prenatal diagnosis of haemoglobinopathies, and emphasize the importance of appropriately applying and interpreting haematological tests in supporting the optimum application and evaluation of globin gene DNA analysis.

A holistic approach to education programs in thalassemia for a multi-ethnic population: consideration of perspectives, attitudes, and perceived needs

Hemoglobin disorders which include thalassemias are the most common heritable disorders. Effective treatment is available, and these disorders can be avoided as identification of carriers is achievable using simple hematological tests. An in-depth understanding of the awareness, attitudes, perceptions, and screening reservations towards thalassemia is necessary, as Malaysia has a multi-ethnic population with different religious beliefs. A total of 13 focus group discussions (70 participants) with members of the general lay public were conducted between November 2008 and January 2009. Lack of knowledge and understanding about thalassemia leads to general confusions over differences between thalassemia carriers and thalassemia major, inheritance patterns, and the physical and psychologically impact of the disorder in affected individuals and their families. Although most of the participants have not been tested for thalassemia, a large majority expressed willingness to be screened. Views on prenatal diagnosis and termination of fetuses with thalassemia major received mixed opinions from participants with different religions and practices. Perceived stigma and discrimination attached to being a carrier emerged as a vital topic in some group discussions where disparity in the answers exhibited differences in levels of participants' literacy and ethnic origins. The two most common needs identified from the discussion were information and screening facilities. Participants' interest in knowing the severity of the disease and assessing their risk of getting the disorder may imply the health belief model as a possible means of predicting thalassemia public screening services. Findings provide valuable insights for the development of more effective educational, screening, and prenatal diagnostic services in the multi-ethnic Asian society.

Attitudes towards prenatal diagnosis and termination of pregnancy for thalassaemia in pregnant Pakistani women in the North of England

OBJECTIVES

Most births of children affected with beta-thalassaemia major in the United Kingdom are to parents of Pakistani origin. A popular explanation for this is that Pakistanis decline termination of pregnancy on religious grounds. However, various factors influence people's attitudes towards prenatal diagnosis and termination of pregnancy, which have not been investigated in a UK Pakistani sample. This study is aimed at exploring the attitudes of pregnant Pakistani women towards prenatal diagnosis and termination of pregnancy for beta-thalassaemia major in the North of England.

METHODS

Forty-three pregnant women tested for thalassaemia carrier status were interviewed following receipt of their test results. Interviews were analysed using the grounded theory approach.

RESULTS

Findings showed: (1) women's awareness of and attitudes towards prenatal diagnosis; (2) the relationship between attitudes towards prenatal diagnosis and termination of an affected foetus; (3) the relationship between attitudes towards termination of pregnancy and religious beliefs, perceptions of severity of the condition, influence of significant others, and (4) the impact of gestational age at the time of the offer of termination of pregnancy.

CONCLUSIONS

Pakistani women's attitudes towards prenatal diagnosis and termination of pregnancy are influenced by various factors, and therefore their religion should not be taken as a proxy for their attitudes either for or against termination of pregnancy.

Thalassemia: current approach to an old disease

This article discusses the approach for recognition, diagnosis, and management of the thalassemias, and reviews new prospects of therapy, focusing mostly on the beta-thalassemias--the more severe and clinically important type, beta-thalassemia major is typically treated with regular transfusion and chelation therapy. New strategies for specific therapy including monitoring of iron induced organ damage, fetal hemoglobin augmentation as an alternative for transfusions, bone marrow transplantation offer hope for prevention of complications and better care of the beta-thalassemias.

"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.

Acceptance of first-trimester prenatal diagnosis for the haemoglobinopathies in Lebanon

We have interviewed 83 couples at risk for a haemoglobin disorder, mostly beta-thalassaemia, in an effort to evaluate their attitude towards first-trimester prenatal diagnosis. Most of the families had received poor education and were of low socio-economic status and more than half of the couples were not properly aware of their genetic risk. Fifty-nine per cent of the couples were definitely in favour of prenatal diagnosis, 23 per cent were uncertain at the time of the interview, and 18 per cent were opposed to such testing, because of their religious conviction against termination of a pregnancy. Another important factor which seems to influence choice was the cost of the test. Essential issues that arise from this study include the importance of a control programme adapted to particular populations, proper information and counselling, and the need for financial support in countries such as Lebanon.

Haemoglobinopathies

The inherited haemoglobinopathies are a heterogeneous group of recessive disorders that include the thalassaemias and sickle cell disease. Nearly a thousand mutant alleles have now been characterized. The mutations are regionally specific and in most cases the geographical and ethnic distributions have been determined providing the foundation for a programme of control through screening, genetic counselling and prenatal diagnosis. The main requirements for methodologies providing molecular diagnosis are speed, cost, convenience and the ability to test for multiple mutations simultaneously. For beta-thalassaemia mutations the procedures that meet these requirements are the amplification refractory mutation system and the reverse dot-blot hybridization system. For alpha-thalassaemia the technique of gap PCR is useful for targeting specific deletion mutations but Southern blotting remains the standard diagnostic test.

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.