Premarital screening of beta-thalassemia trait in the province of Denizli, Turkey

Awareness of sickle cell disease among nursing undergraduates in Farasan: Its interference with malaria

Aim

The present study was conducted to generate data on awareness and incidence of sickle cell disease (SCD) and also to adduce the widespread myths peddled about SCD.

Materials and Methods

Students studying in the Department of Nursing were recruited. A pretested, self-administered sickle cell assessment questionnaire was distributed electronically through WhatsApp group to collect necessary data. Participants were screened for malaria by thin blood smear analyses, and their hemoglobin (Hb) contents (g/dL) were determined by Sahli's haemoglobinometer. Statistical analyses were done using Origin (version 8.1, USA). A reliability study was performed for the validity of questionnaire data.

Results

Study participants had significantly high awareness regarding SCDs (89.9%, P < 0.001). Most participants (96.3%) were aware about government policy regarding premarital screening for genetic disorders and replied that the government has strict health policies backed by equally robust laboratory diagnostics. Moreover, none of the participants had SCDs, although their parents had a consanguineous marriage. Thin blood smear analyses of participants did not reveal any cases of Plasmodium falciparum. However, significant percentages (33.1%) were found to be anemic, probably due to their dietary habits and lifestyles, as has been reflected by questionnaire analyses. Furthermore, a very less number of students had knowledge about genetic variations that might occur in malaria-endemic regions after long exposure to offer protection from malaria. Knowledge about management practices was also lacking among study participants (29%).

Conclusion

This research points to the necessity that the nursing study plan should focus on providing specific training on management skills and preventive measures for SCDs, which is of paramount importance.

Premarital hemoglobinopathy screening program results of a province in the Black Sea region of Turkey: three years' experience

OBJECTIVES

Hemoglobinopathies are a global public health problem with high mortality and morbidity and very expensive treatment. Disease can be reduced and prevented with hemoglobinopathy screening tests. It is possible to identify carriers with the hemoglobinopathy screening program applied in many countries of the world and in Turkey. This study aims to evaluate the results of the national premarital hemoglobinopathy screening program carried out in primary healthcare institutions.

METHODS

The research is of epidemiological and cross-sectional type. Electrophoresis results examined within the scope of the premarital hemoglobinopathy screening program in Samsun between 1 January 2019 and 31 December 2021 were evaluated retrospectively. Age, gender, year of screening, and hemoglobinopathy screening results were obtained from the records. In the statistical analysis of the data, p < 0.05 was accepted.

RESULTS

The median age of 52,338 people screened under the hemoglobinopathy screening program was 29.0 (16.0-86.0) years. About 54.1% (n = 28,309) of those who were screened were female, and it was found that the least screening was done in 2020 (n = 15,765 (30.1%)). As a result of the screening, the frequency of the β-thalassemia (β-thal) trait was 1.37% (n = 676), the frequency of the abnormal HbS was 0.04% (n = 20). The frequency of β-thal trait was statistically significantly higher in 2020 (1.5%) compared to other years (p = 0.029). When the results were analyzed by gender, the rate of women with abnormal HbS (3.7%) was significantly higher than the others (p = 0.017).

CONCLUSIONS

This study presents the results of the national hemoglobinopathy screening program in Northern Turkey and the β-thal and the abnormal HbS rates were found to be low. The data obtained will be useful in monitoring hemoglobinopathy disorders and evaluating the current program's effectiveness in the future. It will allow decision-makers to implement policy changes and prioritize new programs.

Interventions addressing genetic disease burdens within selected countries in the MENA region: a scoping review

BACKGROUND

The MENA region is disproportionately affected by genetic disease. The aim of this research is to scope the region for evidence of genetic services and public health interventions to identify geographic gaps, and to provide a descriptive overview of interventions to identify knowledge gaps.

METHODS

This study is conducted as a scoping review and follows the Arksey & O'Malley scoping review framework.

RESULTS

Seventy-six articles spanning 16 MENA nations met inclusion criteria. Studies included interventions in the form of genetic service provision (n=28), as well as comprehensive programs including pilot programs (n=7), community-based genetics programs (n=6) national-level prevention programs (n=18), and national-level mandatory programs (n=17).

CONCLUSIONS

There is an imbalanced response to genetic disease burdens across the MENA region. More research is warranted where interventions are scarce, particularly to inform development of pilot community-based programs. There is also a need for better monitoring and evaluation of existing nation-wide programs.

Ethical, social, and cultural issues related to clinical genetic testing and counseling in low- and middle-income countries: a systematic review

PURPOSE

We performed a systematic review of the ethical, social, and cultural issues associated with delivery of genetic services in low- and middle-income countries (LMICs).

METHODS

We searched 11 databases for studies addressing ethical, social, and/or cultural issues associated with clinical genetic testing and/or counselling performed in LMICs. Narrative synthesis was employed to analyze findings, and resultant themes were mapped onto the social ecological model (PROSPERO #CRD42016042894).

RESULTS

After reviewing 13,308 articles, 192 met inclusion criteria. Nine themes emerged: (1) genetic counseling has a tendency of being directive, (2) genetic services have psychosocial consequences that require improved support, (3) medical genetics training is inadequate, (4) genetic services are difficult to access, (5) social determinants affect uptake and understanding of genetic services, (6) social stigma is often associated with genetic disease, (7) family values are at risk of disruption by genetic services, (8) religious principles pose barriers to acceptability and utilization of genetic services, and (9) cultural beliefs and practices influence uptake of information and understanding of genetic disease.

CONCLUSION

We identified a number of complex and interrelated ethical, cultural, and social issues with implications implications for further development of genetic services in LMICs.

New Bioinformatics-Based Discrimination Formulas for Differentiation of Thalassemia Traits From Iron Deficiency Anemia

Thalassemia traits (TTs) and iron deficiency anemia (IDA) are the most common disorders of hypochromic microcytic anemia (HMA). The present study aimed to differentiate TTs from IDA by analyzing discrimination formulas and provides comprehensive data of hemoglobin disorders prevalent in Pakistan. Among 12 published discrimination formulas, 6 formulas-MI, EF, G&K, RDWI, R, and HHI-were the most reliable to discriminate TTs from IDA. The failure cutoff values were improved by the random forest (RF) decision-tree approach. Moreover, the Shine and Lal (S&L) formula, which completely failed to discriminate IDA from TTs with original cutoff value (<1530), improved with the use of new proposed cutoff value (<1016) and was found to successfully discriminate all cases of TTs from those with IDA. In addition, 2 newly proposed formulas discriminated TTs from IDA more reliably than the original 12 formulas assessed. The proposed formulas could play a crucial role for clinicians to discriminate between TTs and IDA.

The Frequency of Factor V Leiden and Concomitance of Factor V Leiden With Prothrombin G20210A Mutation and Methylene Tetrahydrofolate Reductase C677T Gene Mutation in Healthy Population of Denizli, Aegean Region of Turkey

Factor V Leiden causing activated protein C resistance is the most common inherited form of thrombophilia leading to thrombosis. Its frequency shows great ethnic and geographic variations. The aim of this study was to determine the frequency of FV Leiden and coinheritance of FV Leiden with two other frequent hereditary thrombophilia causes, namely, prothrombin G20210A and methylene-tetrahydrofolate reductase ( MTHFR) C677T mutation in the Aegean region of Turkey. The study population consisted of 1030 (500 men and 530 women) apparently healthy subjects. Functional resistance to activated protein C (APC) was measured by using the test kit STA staclot APC-R ((Diagnostica Stago, Asnieres, France, Cat. No. 00721). In subjects with APC resistance, molecular analyses of FV Leiden and of prothrombin G20210A and MTHFR C677T mutation were performed by using FV-PTH-MTHFR StripA (Vienna Lab, Labordiagnostika GmbH, Austria) kit, which was based on hybridization of polymerase chain reaction (PCR) amplified DNA products with mutation-specific oligonucleotide probes. Functional APC resistance was present in 93 subjects (9%). FV Leiden mutation was found in 87 of 93 subjects with APC resistance by PCR method. The FV Leiden carrier frequency was found to be 8.4% (87/1030). Seventy-six individuals were heterozygous (7.3%), and 11 were homozygous (1.06%). Among the 87 subjects with FV Leiden mutation, 45 subjects had MTHFR C677T gene mutation (7 homozygous, 38 heterozygous) and 4 subjects had heterozygote prothrombin G20210A gene mutation. A combination of FV Leiden and prothrombin G20210A and MTHFR C677T gene mutation was detected in 3 subjects. The results indicate that FV Leiden prevalence is quite high and coexistence of FV Leiden with other hereditary causes of thrombosis such as prothrombin G20210A mutation and MTHFR enzyme defect is not rare in healthy population of Aegean region of Turkey.

The Prevalence of Hemoglobinopathies in Young Adolescents in the Province of Muğla in Turkey: Results of a Screening Program

Thalassemia is an autosomal recessive inherited blood disorder. It is prevalent in Mediterranean countries such as Sardinia, Greece, Cyprus, Turkey, Lebanon and also Southeast Asia. Our aim was to investigate the carrier prevalence of thalassemia and other hemoglobinopathies in adolescents who live in Muğla Province, Turkey. We analyzed retrospectively the surveys conducted at primary schools between 1997 and 2013. Complete blood count (CBC) and high performance liquid chromatography (HPLC) were used to screen for thalassemia and hemoglobinopathies. Patients were diagnosed as having thalassemia trait if the mean corpuscular volume (MCV) was ≤ 80.0 fL, mean corpuscular hemoglobin (Hb) was ≤ 27.0 pg and Hb A2 levels were ≥ 3.5%. A total of 164,814 students were analyzed. The median age of the students was 13.5 years (minimum 13.0, maximum 14.0). The total number of students with abnormal HPLC results was 5861 (3.8%). There was a significant decrease in the newborn of new thalassemia patients found with screening programs for hemoglobinopathies in Muğla Province from 1997 to 2013. The number of students with abnormal HPLC results for thalassemia, sickle cell disease and other Hb traits were 3.2, 0.15 and 0.4%, respectively. It is important to recognize that including Hb, MCV, red blood cell (RBC) count and HPLC tests for carrier screening are necessary to find hemoglobinopathies. Our study supported that the number of new patients significantly decreased using these screening programs from 1997 to 2013.

Molecular analysis of abnormal hemoglobins in beta chain in Aegean region of Turkey and first reports of hemoglobin Andrew-Minneapolis and Hb Hinsdale from Turkey

OBJECTIVES

The Agean is one of the regions in Turkey where thalassemias and abnormal hemoglobins (Hbs) are prevalent. Combined heterozygosity of thalassemia mutations with a variety of structural Hb variants lead to an extremely wide spectrum of clinical and hematological phenotypes which is of importance for prenatal diagnosis.

METHODS

One hundred and seventeen patients and carriers diagnosed by hemoglobin electrophoresis (HPLC), at risk for abnormal hemoglobinopathies were screened for mutational analysis of the beta-globin gene. The full coding the 5' UTR, and the 3' UTR sequences of beta-globin gene (GenBank accession no. U01317) were amplified and sequenced.

RESULTS

In this study, a total of 118 (12.24%) structural Hb variant alleles were identified in 1341 mutated beta-chain alleles in Medical Genetics Department of Ege University between January 2006 and November 2013.

DISCUSSION

Here, we report the mutation spectrum of abnormal Hbs associated with the beta-globin gene in Aegean region of Turkey.

CONCLUSION

In the present study, the Hb Hinsdale and Hb Andrew-Minneapolis variants are demonstrated for the first time in the Turkish population.

The diminishing trend of β-thalassemia in Southern Iran from 1997 to 2011: the impact of preventive strategies

The marginal zones of the Caspian Sea and the Persian Gulf have a higher prevalence of thalassemia compared to other regions of Iran. This disease has disabled many people and resulted in increasing health care costs. The aim of this study was to assess the incidence of β-thalassemia (β-thal) and to evaluate the outcome of applied preventive strategies over a 14-year period in Fars Province, Southern Iran. This cross-sectional study comprised all new cases of β-thal recorded during 1997-2011. The data were obtained from the Non-Communicable Diseases Surveillance Department of Shiraz University of Medical Sciences, Shiraz, Iran, and are presented as mean ± standard deviation (SD). The Fars Health Network System screened 840 686 males and females applying for marriage certificates. Among the carriers, 50.5% cancelled their marriages, 42.5% married, and 7.0% did not show up at the clinics. The rate of cancelled marriages has reduced since 2000, when marriage candidates were given the option of prenatal diagnosis. From 2000 to 2011, a total of 3539 married couples were referred for prenatal diagnosis. Of these, 806 fetuses were found to carry thalassemia and 800 aborted. It is impressive to note that while 101 cases of thalassemia were recorded in 1997, this figure was reduced to two cases by 2011. This study has established that an integrated primary health care approach, with good infrastructure for implementing successful strategies, can significantly reduce the incidence of β-thal.

The first five years of a preventive programme for haemoglobinopathies in Northeastern Iraq

OBJECTIVE

To evaluate the feasibility and effectiveness of a preventive programme for haemoglobinopathies in a single centre in Northeastern Iraq.

METHODS

Premarital screening, genetic counselling and prenatal diagnosis (PND) were implemented over a 5 year period.

RESULTS

Among 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.

CONCLUSION

The 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.

Unique pattern of mutations in β-thalassemia patients in Western Uttar Pradesh

CONTEXT

β-thalassemia is one of the most common heterogeneous inherited single gene disorders. The disease results from one or more of 380 different mutations in the β-globin gene. Uttar Pradesh (U.P.) is the most populous state of India, comprising various ethnic groups and Bareilly is one of the largest cities situated in Western U.P.

AIMS

To examine the prevalence of five common β-thalassemian mutations: Intervening Sequence IVS 1-5 (c. 92 + 5 G > C), codon 8/9 (c. 27_28insG), codon 41/42 (c. 124_127delTTCT), IVS 1-1 (c. 92 + 1 G > T) and codon 26 G-A (c. 79G > A) in Western U.P.

SETTINGS AND DESIGN

Patients attending camps organized by the Thalassemia Society, Bareilly were selected for the study.

MATERIALS AND METHODS

A total of 48 blood samples were collected from the patients of transfusion dependent β-thalassemia from July 2011 to May 2012. All the samples were analyzed for five common mutations by using the Amplification Refractory Mutation System (ARMS)-hot start-polymerase chain reaction (PCR) technique.

RESULTS

Among the five common mutations prevalent in India, we were able to detect all except codon 26 G-A (c. 79G > A), which is prevalent in northeast India. These four mutations accounted for 58% of the total number of our patients. The IVS 1-5 (G-C) was found to be the most common mutation with a frequency of 46% and the 2 (nd)most common mutation was Fr8/9 (+G) with a frequency of 21%. The frequency of other mutations was IVS1-1 (12%) and Cd 41/42 (4%).

CONCLUSION

This study provides evidence that the pattern of mutations in Western U.P. is different from the rest of India and even from the neighboring states (Delhi and Punjab). To the best of our knowledge, mutation Fr8/9, the 2(nd)most common mutation in our study has never been reported to be so common from anywhere in India. Some mutations, which are prevalent in other regions are absent in our region (mutation for ε-globin). Hence, these findings can be called unique to Western U.P.

Prevalence of β-thalassemia trait and abnormal hemoglobin in premarital screening in the province of Izmir, Turkey

BACKGROUND/AIMS

Thalassemia is one of the most common hereditary disorders in Turkey. The aim of our study was to determine the prevalence of the β-thalassemia trait and abnormal hemoglobin in couples who applied for premarital screening in the third largest Turkish province of Izmir in the Aegean region.

METHODS

From January 2011 to March 2012, we tested 19,277 couples at the Karşıyaka Public Health Laboratory, Thalassemia Unit for the β-thalassemia trait and abnormal hemoglobin using a high-performance liquid chromatograph, a hematology analyzer.

RESULTS

The β-thalassemia trait with increased HbA2 (>3.5%) and abnormal hemoglobin was found in 4.96% (1912/38,554) and 0.53% (206/38,554) people, respectively. Of abnormal hemoglobin findings, HbS was determined in 128 people (0.33%), HbD in 50 (0.13%), HbE in 24 (0.06%), and HbC in four (0.01%). Furthermore, in 20 of the 19,277 couples (0.05%), both partners had the β-thalassemia trait and were referred to counseling.

CONCLUSION

The prevalence of the β-thalassemia trait in the province of Izmir is high compared with other cities of Turkey. Izmir is a high-risk province for β-thalassemia and sickle-cell anemia. Therefore, premarital screening is essential to prevent new hereditary hemoglobinopaties.

Six-year outcome of the national premarital screening and genetic counseling program for sickle cell disease and β-thalassemia in Saudi Arabia

BACKGROUND AND OBJECTIVES

Saudi Arabia has a high prevalence of hereditary hemoglobin disorders. Data has been collected by the Saudi Premarital Screening and Genetic Counseling Program on the prevalence of sickle cell disease and β-thalassemia but the outcomes were not quantified. We used six years of premarital screening data to estimate the burden of sickle disease and β-thalassemia over the program period and to assess the frequency of at-risk marriage detection and prevention.

DESIGN AND SETTING

Retrospective review, premarital couples attending premarital and genetic counseling clinics with marriage proposals between 2004 and 2009.

METHODS

Blood samples obtained from all couples with marriage proposals between 2004 and 2009 were tested for sickle cell disease and β-thalassemia. Test results were shared with all examinees and genetic counseling was offered for all at-risk couples. Marriage certificates were issued irrespective of the results and compliance with medical advice was voluntary.

RESULTS

Out of all men and women examined, 70,962 (4.5%) and 29,006 (1.8%) were carriers or cases of sickle cell disease and β-thalassemia, respectively. While the prevalence of sickle cell disease was constant between 2004 and 2009 (average 45.1 per 1000 examined persons, P=.803), the prevalence of β-thalassemia steadily decreased from 32.9 to 9.0 per 1000 examined persons (P<.001). The frequency of at-risk couples decreased by about 60% between 2004 and 2009 (from 10.1 to 4.0 per 1000 examined persons, P<.001). The frequency of voluntary cancellation of marriage proposals among at-risk couples showed more than 5-fold increase between 2004 and 2009 (from 9.2% to 51.9%, P<.001). The eastern region had 58% of all detected at-risk marriages and showed the greatest decline in detection and increase in prevention over time compared to other regions of Saudi Arabia.

CONCLUSION

Six years of premarital screening in Saudi Arabia markedly reduced the number of at-risk marriages, which may considerably reduce the genetic disease burden in Saudi Arabia in the next decades.

Preconceptional genetic carrier testing and the commercial offer directly-to-consumers

Recently, a number of commercial companies are offering preconceptional carrier tests directly-to-consumers. This offer raises a number of concerns and issues above and beyond those encountered with preconceptional tests offered within the traditional health care setting. In order to bring some of these issues to light and to initiate dialogue on this topic, this article discusses the following issues: the current offer of preconceptional carrier tests (until the end of 2010) through online commercial companies; the implications for the informed consent procedure and the need for good information; the need for medical supervision and follow-up; and the appropriate use of existing resources. The article concludes with some reflections about the potential sustainability of the offer of preconceptional carrier tests directly-to-consumers.

Postmarital follow-up survey on high risk patients subjected to premarital screening program in Saudi Arabia

BACKGROUND

Haemoglobinopathies are the most inherited disorders worldwide including Saudi Arabia which can be preventable with application of screening programmers. Ministry of Health in Saudi Arabia had initiated premarital screening program (PMS) in all country regions.

METHODS

The aim of this study was to explore the impact of the PMS program and genetic counseling on couples at risk for thalassaemia and sickle cell anima in an area of the country with high hemoglobinopathy prevalence. A total of 129 candidates identified by PMS to be at risk were included.

RESULTS

Out of this cohort, 98% proceeded with marriage. Culture pressure was the main reason in more than 48%. Over a period of 4 years, these marriages resulted in 15 diseased children. Although most of the candidates did not receive genetic counseling yet, the concept of genetic counseling was liked by most of them.

CONCLUSION

This study showed some early benefits of the PMS in prevention of the targeted diseases and the program helped in early detection of the disease in their offspring.

Carrier screening for beta-thalassaemia: a review of international practice

β-thalassaemia is one of the most common single-gene inherited conditions in the world, and thalassaemia carrier screening is the most widely performed genetic screening test, occurring in many different countries. β-thalassaemia carrier screening programmes provide a unique opportunity to compare the delivery of carrier screening programmes carried out in different cultural, religious and social contexts. This review compares the key characteristics of β-thalassaemia carrier screening programmes implemented in countries across the world so that the differences and similarities between the programmes can be assessed. The manner in which thalassaemia carrier screening programmes are structured among different populations varies greatly in several aspects, including whether the programmes are mandatory or voluntary, the education and counselling provided and whether screening is offered pre-pregnancy or antenatally. National and international guidelines make recommendations on the most appropriate ways in which genetic carrier screening programmes should be conducted; however, these recommendations are not followed in many programmes. We discuss the implications for the ethical and acceptable implementation of population carrier screening and identify a paucity of research into the outcomes of thalassaemia screening programmes, despite the fact that thalassaemia screening is so commonly conducted.

Frequency of β-thalassemia trait and other hemoglobinopathies in northern and western India

INTRODUCTION

India is an ethnically diverse country with an approximate population of 1.2 billion. The frequency of beta-thalassemia trait (βTT) has variously been reported from <1% to 17% and an average of 3.3%. Most of these studies have been carried out on small population groups and some have been based on hospital-based patients. There is also a variation in the prevalence of hemoglobinopathies in different regions and population groups in the country. A high frequency of Hb D has been reported from the North in the Punjabi population, Hb E in the eastern region of India and Hb S is mainly reported from populations of tribal origin from different parts of the country.

OBJECTIVES

To study the gene frequency of βTT and other hemoglobinopathies in three regions East (Kolkata), West (Mumbai) and North (Delhi) in larghe population group (schoolchildren) for a more accurate assessment of gene frequency for planning of control programmes for haemoglobinopathies.

MATERIALS AND METHODS

This study included 5408 children from 11 schools in Delhi, 5682 from 75 schools in Mumbai and 957 schoolchildren from Kolkata who were screened for βTT and haemoglobinopathies. These included 5684 children from 75 schools in Mumbai and 5408 children from 11 schools in Delhi. Children were 11-18 years of age of both sexes. The final report is, however, only on 11090 schoolchildren from Mumbai and Delhi as data from Kolkata was restricted both in numbers and objectives and could not be included for comparison.

RESULTS

The overall gene frequency of βTT in Mumbai and Delhi was 4.05% being 2.68% and 5.47% in children of the two cities respectively. In Mumbai, the gene frequency was evenly distributed. Majority of the children with βTT from Mumbai were from Marathi (38.9%) and Gujarati (25%) speaking groups. Gene frequency was >5% in Bhatias, Khatris, Lohanas and Schedule Castes. In Delhi, a higher incidence was observed in schoolchildren of North and West Delhi (5.8-9.2%). The schoolchildren of North and West Delhi comprised predominantly of Punjabi origin compared to children in the South of the city (2.2%, 2.3%). When analyzed state-wise, the highest incidence was observed in children of Punjabi origin (7.6%) and was >4% from several other states. Majority of the traits from Mumbai were anemic (95.1% male and 85.6% in female). The prevalence of anemia was lower (62.7% male and 58.4% female) children with βTT from Delhi. This was a reflection of the higher prevalence of anemia in children without hemoglobinopathy in Mumbai than in Delhi. Nutritional deficiency was probably more severe and rampant in children Mumbai. Gene frequency of Hb D was greater in schoolchildren from Delhi (1.1%) than in Mumbai (0.7%). Hb S trait (0.2%) was observed exclusively in children from Mumbai. A low incidence of Hb E trait (0.04%) was seen in children in Mumbai. A higher incidence is reported from the East. The number of cases studied from the eastern region was small as the data from the East (Kolkata) could not be included in the analysis.

CONCLUSION

This study comprises a larger number of children studied for the gene frequency of βTT and other hemoglobinopathies from India. Population groups with higher gene frequencies require screening programmes and facilities for antenatal diagnosis as well as increased awareness and educational programmes to control the birth of thalassemic homozygotes. The overall carrier frequency of βTT was 4.05% and reinforces the differential frequency of β-thalassemia trait in schoolchildren from Delhi and Mumbai and the higher incidence of hemoglobin D in Punjabis as reported previously. The birth incidence calculated thereof for homozygous thalassemics would be 11,316 per year which are added each year to the existing load of homozygous thalassemics. This is much higher than the previously reported number of births annually. Hence suitable control measures need to be undertaken urgently in India.

A Confidential Inquiry Estimating the Number of Patients Affected with Sickle Cell Disease and Thalassemia Major Confirms the Need for a Prevention Strategy in The Netherlands

We have conducted a broad confidential inquiry among 401 hospital departments trying to estimate the number of patients affected with severe forms of hemoglobinopathies living in The Netherlands. With less than 30% response we have registered 559 patients in all age categories of whom 77.0% are affected with sickle cell disease and 17.5% with beta-thalassemia (thal) major. We estimate that the real figure could be around 800 patients, a figure more than six times higher than the number published in 1995 on which the reluctance to offer prevention was based. The actual figures and the incidence estimation of approximately 60 patients a year underline the urgent need for the official implementation of a prevention strategy in The Netherlands. During the last 5 years we have been working towards the implementation of a multi-intervention strategy for primary prevention using the existing structures of public health. The obstacles we have encountered to endorse such a strategy are discussed as a possible guide for other immigration countries.

Premarital screening programmes for haemoglobinopathies, HIV and hepatitis viruses: review and factors affecting their success

This literature review is a comprehensive summary of premarital (prenuptial) screening programmes for the most prevalent hereditary haemoglobinopathies, namely thalassaemia and sickle cell disease, and the important infections HIV (human immunodeficiency virus) and hepatitis viruses B and C (HBV and HCV). It describes the background to premarital screening programmes and their value in countries where these diseases are endemic. The use of premarital screening worldwide is critically evaluated, including recent experiences in Saudi Arabia, followed by discussion of the outcomes of such programmes. Despite its many benefits, premarital testing is not acceptable in some communities for various legal and religious reasons, and other educational and cultural factors may prevent some married couples following the advice given by counsellors. The success of these programmes therefore depends on adequate religious support, government policy, education and counselling. In contrast to premarital screening for haemoglobinopathies, premarital screening for HIV and the hepatitis viruses is still highly controversial, both in terms of ethics and cost-effectiveness. In wealthy countries, premarital hepatitis and HIV testing could become mandatory if at-risk, high-prevalence populations are clearly identified and all ethical issues are adequately addressed.

Knowledge and attitude toward the hemoglobinopathies premarital screening program in Saudi Arabia: population-based survey

Genetic screening is an important tool to control, minimize, and prevent genetic disorders. Saudi Arabia started the first national premarital screening (PMS) program to control inherited hemoglobin (Hb) disorders that are the most commonly inherited genetic disorders in the Kingdom of Saudi Arabia. The aim of this study was to assess the knowledge, perception, and attitude among the Saudi population about the PMS program through a questionnaire-based survey. A total of 1,047 candidates were included, divided into three groups. Group A represented the general population, group B was composed of couples presenting for PMS, and group C represented couples who had received their results. There was a fair knowledge among participants of the three groups about the nature of the tests and the targeted disorders, with more than 80% believing that it should include both sexually and genetically transmitted diseases. The concept of genetic counseling was liked by most of the participants. There was a positive attitude toward the program and the majority agreed to apply the PMS program to all couples in all country regions. More than 60% of all the participants were in favor of preventing at-risk marriages.

Carrier Testing for Autosomal- Recessive Disorders

The aim of carrier testing is to identify carrier couples at risk of having offspring with a serious genetic (autosomal recessive) disorder. Carrier couples are offered genetic consultation where their reproductive options, including prenatal diagnosis, are explained. The Ashkenazi Jewish population is at increased risk for several recessively inherited disorders (Tay-Sachs disease, Cystic fibrosis, Canavan disease, Gaucher disease, Familial Dysautonomia, Niemann-Pick disease, Fanconi anemia, and Bloom syndrome). Unlike Tay-Sachs disease, there is no simple biochemical or enzymatic test to detect carriers for these other disorders. However, with the rapid identification of disease-causing genes in recent years, DNA-based assays are increasingly available for carrier detection. Approximately 5% of the world's population carries a mutation affecting the globin chains of the hemoglobin molecule. Among the most common of these disorders are the thalassemias. The global birth rate of affected infants is at least 2 per 1000 (in unscreened populations), with the greatest incidence in Southeast Asian, Indian, Mediterranean, and Middle Eastern ethnic groups. Carriers are detected by evaluation of red cell indices and morphology, followed by more sophisticated hematological testing and molecular analyses. The following issues need to be considered in the development of a carrier screening program: (1) test selection based on disease severity and test accuracy; (2) funding for testing and genetic counselling; (3) definition of the target population to be screened; (4) development of a public and professional education program; (5) informed consent for screening; and (6) awareness of community needs.

Thalassaemia screening in a non-prevalent region of a prevalent country (Turkey): is it necessary?

OBJECTIVES

Haemoglobinopathies are the most widespread inherited disorders in the world, and are also common in Turkey. Haemoglobinopathies are preventable with control programmes. Therefore, the Ministry of Health initiated a control and prevention programme in 33 provinces in Turkey. The aim of this study was to determine the frequency of haemoglobinopathies in Erzurum as part of the programme mentioned above, and to discuss the need for premarital screening in a non-prevalent region (Erzurum) of a prevalent country (Turkey) as part of a national control programme.

STUDY DESIGN

Epidemiological and descriptive survey.

METHODS

This study was conducted between May 2005 and February 2006 in Erzurum. Subjects were couples who attended for premarital screening. All blood samples were measured by high-performance liquid chromatography (HPLC) to determine haemoglobinopathies.

RESULTS

In total, 1610 individuals were screened. The frequency of beta-thalassaemia trait was 0.68%. Haemoglobin D was the most common (0.12%) abnormal haemoglobin. Haemoglobins S, C and E were not detected. The frequency of beta-thalassaemia trait and other haemoglobinopathies in Erzurum was quite low compared with other provinces in Turkey.

CONCLUSIONS

Premarital haemoglobinopathy screening should not be mandatory in a non-prevalent region of a prevalent country as part of a national control programme. If screening is mandatory, it should be performed by total blood count or enzyme-linked immunosorbent assay, which are simple, rapid and less expensive than HPLC.

Implementation of preconceptional carrier screening for cystic fibrosis and haemoglobinopathies: a sociotechnical analysis

OBJECTIVE

To obtain more insight into the process of potential implementation of a screening program, which aims to identify carriers of cystic fibrosis and haemoglobinopathies before pregnancy, in order to enable couples at high risk of having a child with these disorders, to make informed reproductive decisions.

METHODS

Use of sociotechnical analysis, based on a model of co-evolution between technology and society, and, for comparison, the study of the implementation processes of two already existing health care programs with similar aspects to the screening program at issue.

RESULTS

Factors important for success appeared to be the existence of sociotechnical niches, in which technological options can be developed and studied in an experimental setting; a structural approach of providing information to future parents; a party that can articulate demand; governmental involvement in the attunement between various stakeholders; and a screening infrastructure in which large-scale DNA diagnostic services are available.

CONCLUSIONS

Successful implementation of preconceptional carrier screening for cystic fibrosis and haemoglobinopathies will depend on changes at both regime and landscape level, including the establishment of a new preconceptional health care setting and a clearly visible public health authority which can coordinate, monitor and evaluate such an initiative in public health care.

High incidence of Hb D-Los Angeles [beta121(GH4)Glu-->Gln] in Denizli Province, Aegean region of Turkey

Denizli Province is located in the inner part of the Aegean region of Turkey and is one of the target areas for premarital screening. Here we report the abnormal hemoglobins (Hbs) observed during a premarital screening program in our region. According to our results, Hb D-Los Angeles [beta1211(GH4)Glu-->Gln (GAA-->CAA] (also known as D-Punjab, D-North Carolina, D-Portugal, Oak Ridge and D-Chicago), is the most frequent abnormal Hb in this region.

Estimating the attitude of immigrants toward primary prevention of the hemoglobinopathies

OBJECTIVES

We conducted population specific confidential enquiries among immigrants who had never experienced hemoglobinopathies, to study the reliability of this approach in estimating the wish for primary prevention by prenatal diagnosis and selective abortion.

METHODS

We collected data from Surinamese Hindustanis (n = 119), Surinamese and Antillean Afro-Americans (n = 105) and North Africans (mainly Moroccans) (n = 102), living in Holland. We also interviewed 105 informed individuals of different ethnicities, all members of the multi-ethnic patients and carriers' organization 'OSCAR Nederland'.

RESULTS

On average, 68% of the Surinamese Hindustanis and 42% of the Surinamese Afro-Americans were in favor of selective abortion in case of affected pregnancy. Remarkably, 77% of the last group wanted to be tested for carrier diagnostics and 67% declared to have knowledge of the disease before they were informed. Only 16% of the Moroccans were in favor of selective abortion in case of an affected fetus, while 79% wanted to have blood analysis to establish their carrier status.

CONCLUSIONS

The apparently limited wish for selective abortion expressed by Moroccans is in contrast with the high number of illegal abortions reported among married women in Morocco (39%). The wish for selective abortion among informed members of the patients' organization was more than 80%.

Molecular genetic testing of beta-thalassemia patients of Indian origin and a novel 8-bp deletion mutation at codons 36/37/38/39

Hemoglobinopathies are the most commonly inherited genetic disorders in India. Certain communities in India have a high predisposition to beta-thalassemia. To offer prenatal diagnosis and to prevent the birth of an affected child, mutation testing in clinically diagnosed beta-thalassemia patients/carriers is a prerequisite. Over a period of 4 years, we have conducted DNA analysis in 385 carriers for 15 beta-thalassemia mutations, HbD, HbE, and HbS. Using reverse dot blot (RDB) and amplification refractory mutation system (ARMS), we have been able to identify mutations in 381 of 385 thalassemia chromosomes. The study included the analysis of five common mutations found in Asian Indians, namely IVS1-5 (G-C), 619-bp deletion, IVS1-1 (G-T), and the frameshifts at CD8/9(+G) and CD41/42(-CTTT). The occurrence of these five mutations was seen in 299 (91.2%) carriers referred to us, the percentage of mutations varying between 4.0 and 68.9%. We also found Cd16 (-C) in 2.1%, CD30 (G-C) in 1.5%, and CD 15(G-A) in 0.6%; these are considered common mutations in the Indian population, as well. The beta-thalassemia anomaly in 4 (0.6%) carriers remained uncharacterized by RDB and ARMS analysis. During delineation of the mutations in uncharacterized carriers by single-stranded conformational polymorphism (SSCP) and sequencing analysis, we have also been able to identify two unusual mutations, one involving an initiation codon and the second involving a novel 8-bp deletion, in Indian families of Uttar Pradesh origin.