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Objective To determine the prevalence of α-thalassaemia in β-thalassaemia individuals in a Chinese population. Methods The standard diagnostic marker for β-thalassaemia was elevation of the Hb A2 level (>3.5%) with low mean corpuscular volume. The common α-thalassaemia mutations were studied by molecular analysis in all identified β-thalassaemia carriers. Results A prevalence rate of 3.3% for β-thalassaemia was found in our population; α- and β-thalassaemia interactions were found to co-exist in 17.8% of the β-thalassaemia carriers. The -SEA deletion was the most common α-thalassaemia mutation co-inherited with β-thalassaemia, followed by the -α3.7 deletion, the -α4.2 deletion, Hb Quong Sze, and Hb Constant Spring. Conclusion Our results suggest that it could be valuable to study co-existing α-globin mutations in subjects with β-thalassaemia trait in a prenatal screening programme, especially in populations with a high prevalence of haemoglobinopathies.

Background: β-thalassaemia is a preventable disease. Iran has about 20,000 homozygote β-thalassaemia patients and 3,750,000 carriers. Objective: To assess the 10-year results of the screening programme, which has been operating in Southern Iran since 1995. Methods: All couples wanting to marry were required to be checked for β-thalassaemia by their red blood cell indices in order to receive a permit for marriage registration. The results were reported to the nearest counselling team. If the results were conspicuous, haemoglobin A2(HbA2) and, in some subjects, Hb electrophoresis was performed. Couples in which both partners were carriers received counselling. For those who, in spite of the recommendation, decided to marry, prenatal diagnosis and termination of pregnancy in case of an affected fetus was offered. The latter was offered only in the last three years. Results: In 1995, 1999 and 2004, 296, 94 and 56 β-thalassaemia homozygotes, respectively, were born (2.53, 1.07 and 0.82 patients per 1000 births). Discussion: This programme has decreased the birth prevalence of β-thalassaemia, but has unfortunately not eliminated the disease altogether. The reasons for the birth of new cases, in spite of the screening programmes, are: (i) premarital screening programme started in 1995; therefore, carrier couples who married before this did not receive counselling and gave birth to homozygote β-thalassaemia children; (ii) unwanted pregnancy among the carrier couples; (iii) the couples knew about their problem, but they married for cultural and religious causes (illegal marriages).

Objective To evaluate universal antenatal screening for haemoglobinopathies. Setting District general hospital serving a London borough with 45% ethnic minorities. Methods Retrospective cohort study of 1444 women referred in 1688 pregnancies and 95 tertiary referrals during 101 pregnancies. Results Unselected women at risk for sickle cell disease booked 2.7 weeks (95% confidence interval (CI) 0.14 to 5.1) later in gestation than those at risk for β thalassaemia were less likely to attend counselling (83% v93%, relative risk (RR) 0.89; 95% CI 0.85 to 0.94), their partners were less likely to be tested (77% v 95%, RR 0.81; 0.77 to 0.83), and they were less likely to accept prenatal diagnosis (22% v 90%, RR 0.37; 0.24 to 0.57). Over 99% of tertiary referrals attended counselling and had their partners tested. There were no significant differences in acceptance of prenatal diagnosis between those at risk of sickle cell disease and β thalassaemia (55% v 67%). Unselected women at risk of sickle cell disease were significantly less likely to have their partner tested or to accept prenatal diagnosis than tertiary referrals, but not those at risk of β thalassaemia. 80% of β thalassaemia and 16% of SS births were prevented. Conclusions Uptake of prenatal diagnosis among unselected women at risk of β thalassaemia is similar to that reported by tertiary centres. It is considerably lower for sickle cell disease but could increase considerably if screening occurred earlier in gestation. Acceptance of counselling is universally high, suggesting that informed choices are made, and indicating a need to measure these outcomes for cost effectiveness studies.

ObjectiveTo evaluate the feasibility and effectiveness of a preventive programme for haemoglobinopathies in a single centre in Northeastern Iraq.MethodsPremarital screening, genetic counselling and prenatal diagnosis (PND) were implemented over a 5 year period.ResultsAmong a total of 108,264 screened individuals (54,132 couples), β-thalassaemia trait, δβ-thalassaemia trait, and sickle cell trait were diagnosed in 3.98%, 0.11% and 0.07%, respectively. Of 130 at risk couples (2.4/1000), 107 (82%) were available for follow up, with 105 couples (98.1%) proceeding with their marriage after counselling. In the 125 registered pregnancies in the latter couples, PND was performed in 85 (in 80 couples, uptake 76%). Selective termination was chosen in 10 of the 11 pregnancies with an affected fetus. Six affected babies were born among couples who declined PND. At the same time 30 already married couples with at least one thalassaemic child underwent PND, revealing three affected fetuses; all three pregnancies were terminated.ConclusionThe programme revealed that most at risk couples diagnosed by premarital screening chose to proceed with their marriage, with 76% seeking PND followed by selective termination of an affected fetus. A 65% reduction in number of affected births was reported over the 5 year period. This regional programme could serve as a prototype for a national haemoglobinopathy prevention programme.

Objective Despite premarital screening, prenatal diagnosis and the option for voluntary termination of pregnancy, some Iranian couples continue a pregnancy with a fetus affected with beta-thalassaemia major (β-TM). We examined the reasons for this decision, to evaluate the sociocultural challenges these couples face. Methods A retrospective evaluation of medical records of all fetuses aborted was conducted to identify those with β-TM, to determine the frequency of β-TM births and to establish the number of couples with β-thalassaemia who declined prenatal diagnosis or a termination of pregnancy in this period. We investigated the reasons for declining these options. Results The birth prevalence of β-TM decreased from 39.38 to 2.68 in 100,000 live births from 2005 to 2010. Terminations of pregnancy for affected fetuses increased from 67 in 2005 to 135 in 2010. We identified eight couples as β-thalassaemia carriers who declined prenatal diagnosis or a termination of pregnancy. All but one couple already had a child with β-TM. The reasons for declining prenatal diagnosis were strong religious beliefs, superstition and faith in a supernatural solution in six couples. Economic and cultural factors, and previous termination of pregnancy were also mentioned as reasons by the other two couples. Conclusion Although most of the couples had a β-TM child and related socioeconomic problems, their reasons for refusing prenatal diagnosis or termination remain a challenge for the healthcare system in Iran. Couple screening and educational programmes have effectively decreased the rates of refusal in at-risk couples in recent years.