Consanguineous marriages potentially play an important role in the transmission of β-thalassaemia in many communities. This study aimed to determine the rate and socio-demographic associations of consanguineous marriages and to assess the influence on the prevalence of β-thalassaemia in Sri Lanka. Three marriage registrars from each district of Sri Lanka were randomly selected to prospectively collect data on all couples who registered their marriage during a 6-month period starting 1st July 2009. Separately, the parents of patients with β-thalassaemia were interviewed to identify consanguinity. A total of 5255 marriages were recorded from 22 districts. The average age at marriage was 27.3 (±6.1) years for males and 24.1 (±5.7) years for females. A majority (71%) of marriages were ‘love’ marriages, except in the Moor community where 84% were ‘arranged’ marriages. Overall, the national consanguinity rate was 7.4%. It was significantly higher among ethnic Tamils (22.4%) compared with Sinhalese (3.8%) and Moors (3.2%) (p < 0.001). Consanguinity rates were also higher in ‘arranged’ as opposed to ‘love’ marriages (11.7% vs 5.6%, p < 0.001). In patients with β-thalassaemia, the overall consanguinity rate was 14.5%; it was highest among Tamils (44%) and lowest among Sinhalese (12%). Parental consanguinity among patients with β-thalassaemia was double the national average. Although consanguinity is not the major factor in the transmission of the disease in the country, emphasis should be given to this significant practice when conducting β-thalassaemia prevention and awareness campaigns, especially in high-prevalence communities.

The migration of individuals and populations was a powerful factor in the spread of diseases among early human societies. Analysis of human remains from Tell Masaikh in the Middle Euphrates Valley provides a striking example in what is probably the earliest case of hereditary anaemia. Skeletal changes were consistent with thalassaemia, an uncommon disease in the steppe areas of Syria. Genetic analyses of the remains confirmed the pathological assessment and also suggested that the individual was of Asian descent, from the Indian Peninsula. Such an ancestry could then explain this unusual occurrence of thalassaemia.

An anonymous survey of Australian Fellows of the Royal Australian and New Zealand College of Obstetricians and Gynaecologists was conducted with the aim of understanding current practice and attitudes toward population-based carrier screening for inherited conditions in the setting of routine pregnancy care. Of 1,121 Fellows invited to complete the online questionnaire by e-mail, 237 (21%) responded, and of these 156 were practicing obstetricians and completed the whole survey. Of the respondents, 83% expressed support for population-based carrier screening for at least some conditions, with 97% supporting carrier screening for β-thalassaemia, and 83% supporting carrier screening for cystic fibrosis (CF). A small proportion of obstetricians reported offering carrier screening as part of routine pregnancy care (20% for β-thalassaemia, 8% for CF, 5% for fragile X syndrome, and 2% for spinal muscular atrophy). The main practical barriers identified for screening were cost, time constraints, and availability of supporting services. Addressing these issues is crucial for the successful implementation of population-based carrier screening programs in Australia and internationally.

As the results of the Human Genome Project are realized, it has become technically possible to identify carriers of numerous autosomal and X-linked recessive disorders. Couples at risk of having a child with one of these conditions have a number of reproductive options to avoid having a child with the condition should they wish. In Australia the haemoglobinopathies are the only group of conditions for which population screening is widely offered and which is government funded. In some Australian states there are also population screening programs for cystic fibrosis and autosomal recessive conditions more common in Ashkenazi Jewish individuals which are generally offered on a user pays basis. It is predicted that as consumer demand increases and testing becomes cheaper, that many people planning or in the early stages of pregnancy will have carrier screening for multiple genetic conditions. This will have significant implications for genetic counseling, laboratory and prenatal testing resources. In addition such screening raises a number of ethical issues including the value of lives of those born with genetic conditions for which screening is available.

As our communities become more and more diverse, those undertaking research into community nursing practice have a responsibility to incorporate a multi-ethnic perspective into their studies. Primary Care NHS Trusts are increasingly powerful institutions in respect to addressing the needs of minority ethnic groups. As with other public bodies, they need to demonstrate that they are promoting race equality in order to comply with the Race Relations (Amendment) Act 2000. Research into the experiences of families affected by sickle cell disorders and thalassaemia are employed to illustrate nursing accountability for the quality of patient and client care.

Thalassaemias result from mutations of the globin genes that cause reduced or absent haemoglobin production and thus interfere with the critical function of oxygen delivery. They represent the most common single-gene disorders, with 4.83% of the world population carrying globin gene variants. Reduced or absent α-globin (α-thalassaemia) or β-globin (β-thalassaemia) leads to anaemia and multifaceted clinical syndromes. In this second of two reviews on the pathophysiology of haemoglobinopathies, we describe the clinical features, pathophysiology and molecular basis of α- and β-thalassaemias. We then discuss current targeted therapies, including the new oral iron chelators, which, along with chronic transfusions, constitute the mainstay of symptomatic therapy for the majority of patients. Finally, we describe potentially curative therapies, such as bone marrow transplant, and discuss some of the outstanding research studies and questions, including the upcoming field of gene therapy for β-thalassaemia. An accompanying article on haemoglobinopathies (Part I) focuses on sickle cell disease.

In sickle cell disease, a single base pair substitution in the gene encoding the β-globin chain of the haemoglobin molecule gives rise to a surprisingly broad spectrum of pathophysiological and clinical manifestations. Inflammation, endothelial activation, red blood cell membrane abnormalities and altered availability of vasoactive factors characterise this disorder. Clinically, patients suffer from a host of seemingly unrelated maladies, from pain episodes to strokes, life-threatening infections and pulmonary hypertension. Deepened understanding of this complex disease now allows us to begin to turn away from simple supportive treatments, and move towards therapies aimed at specific pathophysiological targets. This article, the first of two reviews on the pathophysiology of haemoglobinopathies, discusses the molecular basis of sickle cell disease, and elaborates on the many factors that exacerbate or ameliorate the disease process. It then focuses on the promising targeted therapies currently in use or under investigation. An accompanying article on haemoglobinopathies (Part II) focuses on thalassaemias.

Dor Yeshorim, a genetic testing programme focusing on the ‘genetic compatibility’ of prospective couples in Orthodox Jewish communities in Europe, the US and Israel, is at the centre of our paper. We discuss the specific understandings of risks that enable the effective implementation of the Dor Yeshorim model in Orthodox populations. Furthermore, we compare Dor Yeshorim to the premarital genetic testing programme for thalassaemia in Cyprus and analyse the particular social practices which generate different notions of genetic identity in these two projects. In the Cypriot programme, where individual carrier status is disclosed, unfavourable genetic carrier status is conceptualized on the individual level and often solved by resorting to prenatal genetic diagnosis upon pregnancy. In the case of Dor Yeshorim, where no information on carrier status but only on the ‘genetic compatibility’ of both partners is revealed, a notion of ‘genetic couplehood’ arises which conceptualizes ‘genetic risk’ not individually but as a matter of genetic jointness. If a prospective couple is found out to be ‘genetically incompatible’, marriage plans usually are cancelled. Furthermore, by not disclosing individual carrier information, Dor Yeshorim successfully avoids a pressing issue which ‘secular’ genetic testing programmes struggle with: the peril of ‘knowing too much’.

The role of oxidant stress in mediating the protection against malaria in thalassaemic red blood cells (RBC) has been hypothesized. In this study we have assessed the relationship between oxidant stress, red cell age and malarial parasite activity in thalassaemic RBC. Using a flow cytometric method to assess lipid peroxidation, we have shown that the age-related increase in sensitivity to oxidative stress previously demonstrated in normal RBC also occurs in thalassaemic RBC. Invasion and growth of Plasmodium falciparum was also shown to deteriorate with increasing RBC age. This effect was more pronounced in thalassaemic RBC with associated schizont maturation arrest and abnormal parasite morphology. In addition, there was a slight but consistent inverse correlation between sensitivity to oxidant stress and parasite activity (R=−0·43; P=0·03 for normal RBC and R=−0·42; P=0·01 for thalassaemic RBC). Our findings indicate an association between red cell age, oxidant stress and P. falciparum growth, providing further support for the role of oxidant stress in mediating the protective effect against malaria in thalassaemic RBC.