RESUMEN
INTRODUCTION: A high frequency of ß-thalassemia in Lao People's Democratic Republic necessitates the importance of complete molecular data before a prevention and control program could be established. Limited data are available for Lao PDR. We have now reported an extended information on the molecular basis of ß-hemoglobinopathies in this population. METHODS: The study was done on 519 unrelated Laos subjects requested for thalassemia investigation. Hematological data were recorded. Hb profiles were obtained using a capillary electrophoresis system. α-And ß-globin genotyping was performed using PCR and related techniques. RESULTS: Among the 519 subjects, 287 (55.3%) were found to carry ß-hemoglobinopathies based on Hb and DNA analyses. These included Hb E carriers (n = 135), homozygous Hb E (n = 47), ß-thalassemia carriers (n = 70), Hb E-ß-thalassemia (n = 25), homozygous ß-thalassemia (n = 4), heterozygous δß0 -thalassemia (n = 2), and carriers of the ß-Hb variant (n = 3). Mutation analysis identified in addition to the Hb E, 8 different ß-thalassemia mutations including codon 17 (A-T), codons 41/42 (-TTCT), NT-28 (A-G), codons 71/72 (+A), IVS1-1 (G-T), 3.4 kb deletion, an initiation codon (T-G) and IVS2-654 (C-T). Two δß0 -thalassemia carriers (12.6 kb deletion) and three subjects with Hb Hope (ß136GGT-GAT ) were identified. Hematological features associated with these ß-hemoglobinopathies were presented. CONCLUSION: ß-hemoglobinopathies in the Laos population is heterogeneous. This information is relevant for setting up a molecular diagnostics and can provide a basis for genetic counseling and enable prenatal diagnosis.
Asunto(s)
Hemoglobinas/genética , Talasemia beta/diagnóstico , Análisis Mutacional de ADN , Femenino , Hemoglobina E/genética , Humanos , Laos/epidemiología , Masculino , Mutación , Globinas alfa/genética , Globinas beta/genética , Talasemia beta/epidemiología , Talasemia beta/genética , Talasemia beta/prevención & controlRESUMEN
The burden of ß-thalassemia (ß-thal) is largely underestimated in India with a carrier frequency of 3.0-4.0% in general, whereas highly stratified frequencies of up to 17.0% are reported in local endogamous subpopulations. We have no idea whether ß-thal carrier frequencies or ß-thal major (ß-TM) births are increasing or decreasing in the population. The cross-sectional nature of all carrier screening programs including large-scale task force and micro level, lack of registration of ß-TM births and mechanism to modulate knowledge, awareness programs in a long-term perspective, all preempt impact assessment of preventive programs. During the implementation of a Telangana State Government-sponsored program on 'Micro profiling of ß-thalassemia mutations in Telangana,' we documented extensive in-depth demographic information on each ß-TM child of the study sample that included age-sex distributions, parental and grand-parental ethnic affiliations (local endogamous group level), birth places, marital migrations, endogamy and consanguinity to identify high-risk districts as ethno-geographic regions. In Telangana State, we found ß-thal is widely prevalent in 31 districts and 48 local endogamous subpopulations. The present study provided a method of identification of four 'high-risk districts' and developed a district model for prevention on high priority in Telangana State. The model has the advantage of impact-assessment of all preventive programs in the district.
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Talasemia beta/etiología , Talasemia beta/prevención & control , Femenino , Humanos , India/epidemiología , Masculino , Modelos Teóricos , Vigilancia en Salud Pública , Medición de Riesgo , Factores de Riesgo , Talasemia beta/epidemiologíaRESUMEN
ß-thalassemia major is an inherited hemoglobinopathy that requires lifelong red blood cell transfusions and iron chelation therapy to prevent complications due to iron overload. Traditionally, ß-thalassemia has been more common in certain regions of the world such as the Mediterranean, Middle East, and Southeast Asia. However, the prevalence of ß-thalassemia is increasing in other regions, including Northern Europe and North America, primarily due to migration. This review summarizes the available data on the changing incidence and prevalence of ß-thalassemia as well as factors influencing disease frequency. The data suggest that the epidemiology of ß-thalassemia is changing: Migration has increased the prevalence of the disease in regions traditionally believed to have a low prevalence, while, at the same time, prevention and screening programs in endemic regions have reduced the number of affected individuals. Various approaches to prevention and screening have been used. Region-specific prevention and treatment programs, customized to align with local healthcare resources and cultural values, have been effective in identifying patients and carriers and providing information and care. Significant challenges remain in universally implementing these programs.
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Talasemia beta/epidemiología , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Emigración e Inmigración , Geografía Médica , Salud Global , Humanos , Incidencia , Vigilancia de la Población , Prevalencia , Vigilancia en Salud Pública , Factores de Riesgo , Talasemia beta/diagnóstico , Talasemia beta/etiología , Talasemia beta/prevención & controlRESUMEN
BACKGROUND: Beta (ß)-thalassemia is one of the most common inherited disorders worldwide, with high prevalence in the Mediterranean, the Middle East and South Asia. Over the past 40 years, awareness and prevention campaigns in many countries have greatly reduced the incidence of affected child births. In contrast, much remains to be done in South-Asia. Thus, for Pakistan, an estimated ~ 7000 children annually are born with thalassemia, with no sign of improvement. Although there is good agreement that intermarriage of carriers significantly contributes to the high prevalence of the disorder, effective tools for molecular screening and diagnosis on which to base prevention programs are not readily available. METHODS: Here, we present results for a novel LeanSequencing™ process to identify a combination of 18 ß-thalassemia mutations (including the sickle cell anemia mutation, HbS, and structural variants HbC and HbE) and 2 hemochromatosis mutations in a multi-ethnic population of 274 pediatric and adolescent patients treated at Afzaal Memorial Thalassemia Foundation in Karachi, Pakistan. RESULTS: We found substantial differences in the predominance of disease-causing mutations among the principal ethnic groups in our cohort. We also found the hemochromatosis mutation H63D C > G in 61 (or 22.1%) of our patients including 6 (or 2.2%) homozygotes. CONCLUSIONS: To our knowledge, this is the first screen combining a large set of ß-thalassemia and hemochromatosis mutations, so as to facilitate the early identification of patients who may be at increased potential risk for complications from iron overload and thereby to improve the prospective management of thalassemia patients.
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Predisposición Genética a la Enfermedad , Hemocromatosis/genética , Mutación , Talasemia beta/genética , Talasemia beta/prevención & control , Adolescente , Adulto , Alelos , Niño , Preescolar , Análisis Mutacional de ADN , Manejo de la Enfermedad , Femenino , Genotipo , Hemocromatosis/diagnóstico , Hemocromatosis/terapia , Hemoglobinas Anormales/genética , Humanos , Lactante , Masculino , Adulto Joven , Talasemia beta/diagnóstico , Talasemia beta/terapiaRESUMEN
Microcytic anemia in children is commonly attributed to iron deficiency without attempting to find the cause. Inadequate investigations to exclude hemoglobinopathies lead to missed opportunities for identification of thalassemia carriers. Here we aim to describe the relative contribution of iron deficiency and thalassemia to microcytic anemia in children. This hospital-based prospective study was conducted at the Colombo North Teaching Hospital, Ragama, Sri Lanka. All newly diagnosed patients with microcytic anemia were recruited and data were collected using an interviewer-administered questionnaire. Full blood count, blood film, serum ferritin, c-reactive protein, quantification of hemoglobin sub-types and α-globin genotype were performed using 4 ml of venous blood. A total of 104 children (Male- 60.5%) were recruited. Iron deficiency was the cause for anemia in 49% whilst 16% and 10% had α- and ß-thalassemia trait respectively. Seven (6.7%) children had co-existing iron deficiency and thalassemia trait while two coinherited α- and ß-thalassemia trait. Children with ß-thalassemia trait had significantly higher red cell count and lower mean corpuscular volume compared to children with iron deficiency. However, none of the red cell parameters were significantly different between children with α-thalassemia trait and iron deficiency. Iron deficiency contributes only to half of children with microcytic anemia; one-fourth had thalassemia trait. Co-existence of iron deficiency and thalassemia trait or co-inheritance of α- and ß-thalassemia trait were found in 9%. Parallel investigation of children with microcytic anemia to diagnose iron deficiency and thalassemia provides an opportunity to identify thalassemia carriers which is beneficial for thalassemia prevention.
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Anemia Ferropénica , Países en Desarrollo , Talasemia alfa , Talasemia beta , Anemia Ferropénica/sangre , Anemia Ferropénica/epidemiología , Anemia Ferropénica/prevención & control , Recuento de Células Sanguíneas , Preescolar , Femenino , Humanos , Lactante , Masculino , Estudios Prospectivos , Sri Lanka , Globinas alfa/metabolismo , Talasemia alfa/sangre , Talasemia alfa/epidemiología , Talasemia alfa/prevención & control , Talasemia beta/sangre , Talasemia beta/epidemiología , Talasemia beta/prevención & controlRESUMEN
Consanguineous marriages potentially play an important role in the transmission of ß-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 ß-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 ß-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 ß-thalassaemia, the overall consanguinity rate was 14.5%; it was highest among Tamils (44%) and lowest among Sinhalese (12%). Parental consanguinity among patients with ß-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 ß-thalassaemia prevention and awareness campaigns, especially in high-prevalence communities.
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Consanguinidad , Matrimonio , Padres , Talasemia beta/epidemiología , Talasemia beta/prevención & control , Adolescente , Adulto , Anciano , Concienciación , Estudios Transversales , Etnicidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Sri Lanka/epidemiología , Adulto Joven , Talasemia beta/etnología , Talasemia beta/psicologíaRESUMEN
OBJECTIVES: Our aim was to describe the numbers and distribution of patients with different types of thalassemia and to assess the standards of care in all thalassemia treatment centers throughout Sri Lanka and the success of the ongoing prevention programme. METHODS: This cross-sectional island-wide survey was conducted by two trained medical graduates, who visited each thalassemia center to collect data from every patient, using a standardized form. Data was collected through review of patient registers and clinical records. RESULTS: We collected data on 1774 patients from 23 centers. 1219 patients (68.7%) had homozygous ß-thalassemia, 360 patients (20.3%) had hemoglobin E ß-thalassemia, and 50 patients (2%) had sickle ß-thalassemia. There were unacceptably high serum ferritin levels in almost all centers. The annual number of births of patients with ß-thalassaemia varied between 45-55, with little evidence of reduction over 19 years. CONCLUSIONS: Central coordination of the treatment and ultimately prevention of thalassemia is urgently needed in Sri Lanka. Development of expert centers with designated staff with sufficient resources will improve the quality of care and is preferred to managing patients in multiple small units.
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Talasemia/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Calidad de la Atención de Salud , Sri Lanka/epidemiología , Talasemia/epidemiología , Talasemia/terapia , Talasemia beta/epidemiología , Talasemia beta/prevención & control , Talasemia beta/terapiaRESUMEN
Iran, as a country located in the Thalassemia Belt, has made great progress in thalassemia prevention and treatment. The thalassemia prevention program was implemented in 1995 and the country-wide thalassemia treatment network, consisting of 64 medical universities and faculties, is active. The acknowledgment of the status of thalassemia treatment and prevention in Iran can be of significance to researchers of the countries affected with thalassemia. In the present research, the database of the Treatment Deputy Office of the Ministry of Health, Treatment and Medical Education and that of the Hemovigilance Network of the Iranian Blood Transfusion Organization, were used. The data were analyzed using the Statistical Package of the Social Sciences, version 23. The findings show 90.13% reduction in the expected cases of new ß-thalassemia (ß-thal) births in 2015. Moreover, out of 18,983 hemoglobinopathy patients, 17,342 are ß-thal major (ß-TM) and ß-thal intermedia (ß-TI) patients covered by 198 medical centers. Out of the total number of blood donations in Iran, 19.17% are allocated to thalassemia treatment. Iran has reached an acceptable level of success in thalassemia prevention and the preparation of safe and adequate blood. Iran's achievements can be adapted to other developing countries, particularly in the Middle East.
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Talasemia beta/epidemiología , Adolescente , Adulto , Distribución por Edad , Niño , Preescolar , Manejo de la Enfermedad , Femenino , Geografía Médica , Hemoglobinopatías/diagnóstico , Hemoglobinopatías/epidemiología , Hemoglobinopatías/prevención & control , Hemoglobinopatías/terapia , Humanos , Lactante , Irán/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Vigilancia en Salud Pública , Sistema de Registros , Adulto Joven , Talasemia beta/diagnóstico , Talasemia beta/prevención & control , Talasemia beta/terapiaRESUMEN
BACKGROUND: Regularly transfused people with sickle cell disease (SCD) and people with thalassaemia (who are transfusion-dependent or non-transfusion-dependent) are at risk of iron overload. Iron overload can lead to iron toxicity in vulnerable organs such as the heart, liver and endocrine glands; which can be prevented and treated with iron chelating agents. The intensive demands and uncomfortable side effects of therapy can have a negative impact on daily activities and well-being, which may affect adherence. OBJECTIVES: To identify and assess the effectiveness of interventions (psychological and psychosocial, educational, medication interventions, or multi-component interventions) to improve adherence to iron chelation therapy in people with SCD or thalassaemia. SEARCH METHODS: We searched CENTRAL (the Cochrane Library), MEDLINE, Embase, CINAHL, PsycINFO, Psychology and Behavioral Sciences Collection, Web of Science Science & Social Sciences Conference Proceedings Indexes and ongoing trial databases (01 February 2017). We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register (12 December 2017). SELECTION CRITERIA: For trials comparing medications or medication changes, only randomised controlled trials (RCTs) were eligible for inclusion.For studies including psychological and psychosocial interventions, educational Interventions, or multi-component interventions, non-RCTs, controlled before-after studies, and interrupted time series studies with adherence as a primary outcome were also eligible for inclusion. DATA COLLECTION AND ANALYSIS: Three authors independently assessed trial eligibility, risk of bias and extracted data. The quality of the evidence was assessed using GRADE. MAIN RESULTS: We included 16 RCTs (1525 participants) published between 1997 and 2017. Most participants had ß-thalassaemia major; 195 had SCD and 88 had ß-thalassaemia intermedia. Mean age ranged from 11 to 41 years. One trial was of medication management and 15 RCTs were of medication interventions. Medications assessed were subcutaneous deferoxamine, and two oral-chelating agents, deferiprone and deferasirox.We rated the quality of evidence as low to very low across all outcomes identified in this review.Three trials measured quality of life (QoL) with validated instruments, but provided no analysable data and reported no difference in QoL.Deferiprone versus deferoxamineWe are uncertain whether deferiprone increases adherence to iron chelation therapy (four trials, very low-quality evidence). Results could not be combined due to considerable heterogeneity (participants' age and different medication regimens). Medication adherence was high (deferiprone (85% to 94.9%); deferoxamine (71.6% to 93%)).We are uncertain whether deferiprone increases the risk of agranulocytosis, risk ratio (RR) 7.88 (99% confidence interval (CI) 0.18 to 352.39); or has any effect on all-cause mortality, RR 0.44 (95% CI 0.12 to 1.63) (one trial; 88 participants; very low-quality evidence).Deferasirox versus deferoxamineWe are uncertain whether deferasirox increases adherence to iron chelation therapy, mean difference (MD) -1.40 (95% CI -3.66 to 0.86) (one trial; 197 participants; very-low quality evidence). Medication adherence was high (deferasirox (99%); deferoxamine (100%)). We are uncertain whether deferasirox decreases the risk of thalassaemia-related serious adverse events (SAEs), RR 0.95 (95% CI 0.41 to 2.17); or all-cause mortality, RR 0.96 (95% CI 0.06 to 15.06) (two trials; 240 participants; very low-quality evidence).We are uncertain whether deferasirox decreases the risk of SCD-related pain crises, RR 1.05 (95% CI 0.68 to 1.62); or other SCD-related SAEs, RR 1.08 (95% CI 0.77 to 1.51) (one trial; 195 participants; very low-quality evidence).Deferasirox film-coated tablet (FCT) versus deferasirox dispersible tablet (DT)Deferasirox FCT may make little or no difference to adherence, RR 1.10 (95% CI 0.99 to 1.22) (one trial; 173 participants; low-quality evidence). Medication adherence was high (FCT (92.9%); DT (85.3%)).We are uncertain if deferasirox FCT increases the incidence of SAEs, RR 1.22 (95% CI 0.62 to 2.37); or all-cause mortality, RR 2.97 (95% CI 0.12 to 71.81) (one trial; 173 participants; very low-quality evidence).Deferiprone and deferoxamine combined versus deferiprone alone We are uncertain if deferiprone and deferoxamine combined increases adherence to iron chelation therapy (very low-quality evidence). Medication adherence was high (deferiprone 92.7% (range 37% to 100%) to 93.6% (range 56% to 100%); deferoxamine 70.6% (range 25% to 100%).Combination therapy may make little or no difference to the risk of SAEs, RR 0.15 (95% CI 0.01 to 2.81) (one trial; 213 participants; low-quality evidence).We are uncertain if combination therapy decreases all-cause mortality, RR 0.77 (95% CI 0.18 to 3.35) (two trials; 237 participants; very low-quality evidence).Deferiprone and deferoxamine combined versus deferoxamine aloneDeferiprone and deferoxamine combined may have little or no effect on adherence to iron chelation therapy (four trials; 216 participants; low-quality evidence). Medication adherence was high (deferoxamine 91.4% to 96.1%; deferiprone: 82.4%)Deferiprone and deferoxamine combined, may have little or no difference in SAEs or mortality (low-quality evidence). No SAEs occurred in three trials and were not reported in one trial. No deaths occurred in two trials and were not reported in two trials.Deferiprone and deferoxamine combined versus deferiprone and deferasirox combinedDeferiprone and deferasirox combined may improve adherence to iron chelation therapy, RR 0.84 (95% CI 0.72 to 0.99) (one trial; 96 participants; low-quality evidence). Medication adherence was high (deferiprone and deferoxamine: 80%; deferiprone and deferasirox: 95%).We are uncertain if deferiprone and deferasirox decreases the incidence of SAEs, RR 1.00 (95% CI 0.06 to 15.53) (one trial; 96 participants; very low-quality evidence).There were no deaths in the trial (low-quality evidence).Medication management versus standard careWe are uncertain if medication management improves health-related QoL (one trial; 48 participants; very low-quality evidence). Adherence was only measured in one arm of the trial. AUTHORS' CONCLUSIONS: The medication comparisons included in this review had higher than average adherence rates not accounted for by differences in medication administration or side effects.Participants may have been selected based on higher adherence to trial medications at baseline. Also, within the clinical trial context, there is increased attention and involvement of clinicians, thus high adherence rates may be an artefact of trial participation.Real-world, pragmatic trials in community and clinic settings are needed that examine both confirmed or unconfirmed adherence strategies that may increase adherence to iron chelation therapy.Due to lack of evidence this review cannot comment on intervention strategies for different age groups.
Asunto(s)
Anemia de Células Falciformes/terapia , Terapia por Quelación , Quelantes del Hierro/uso terapéutico , Sobrecarga de Hierro/prevención & control , Cooperación del Paciente , Talasemia beta/prevención & control , Adolescente , Adulto , Anemia de Células Falciformes/mortalidad , Benzoatos/uso terapéutico , Niño , Deferasirox , Deferiprona , Deferoxamina/uso terapéutico , Humanos , Sobrecarga de Hierro/etiología , Piridonas/uso terapéutico , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Triazoles/uso terapéutico , Talasemia beta/mortalidadRESUMEN
Due to the high rate of consanguineous marriages in Oman, there is a correspondingly high prevalence of hereditary blood disorders, particularly sickle cell disease and ß-thalassaemia. This article proposes the possibility of implementing mandatory premarital carrier screening for blood disorders in Oman, while giving due consideration to potential social and cultural obstacles. Although the implementation of such legislation would require collaboration between different sectors and may negatively affect the autonomy of certain individuals, mandatory premarital screening would help to alleviate the burden of hereditary blood disorders on the national healthcare system, as well as reduce avoidable suffering among carriers and their families.
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Tamizaje Masivo/métodos , Exámenes Prenupciales/métodos , Anemia de Células Falciformes/genética , Anemia de Células Falciformes/prevención & control , Consanguinidad , Pruebas Genéticas/métodos , Humanos , Tamizaje Masivo/tendencias , Omán , Exámenes Prenupciales/tendencias , Prevalencia , Talasemia beta/genética , Talasemia beta/prevención & controlAsunto(s)
Sistemas CRISPR-Cas/genética , Edición Génica/ética , Edición Génica/métodos , Terapia Genética/ética , Terapia Genética/métodos , Proteína 9 Asociada a CRISPR/genética , Favismo/genética , Favismo/prevención & control , Glucosafosfato Deshidrogenasa/genética , Humanos , Globinas beta/genética , Talasemia beta/genética , Talasemia beta/prevención & controlAsunto(s)
Políticas Editoriales , Ingeniería Genética/ética , Investigación Genética/ética , Genoma Humano , Publicaciones Periódicas como Asunto , Responsabilidad Social , Ensayos Clínicos como Asunto , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Genoma Humano/genética , Mutación de Línea Germinal , Humanos , Publicaciones Periódicas como Asunto/ética , Sistema de Registros , Talasemia beta/genética , Talasemia beta/prevención & controlRESUMEN
OBJECTIVE: To devise a strategy for prevention of beta thalassemia in newborns through reliable screening of indexed families. METHODS: The cross-sectional study was conducted over six months in 2011 and comprised blood samples collected from subjects belonging to different ethnic groups from families of beta thalassemia major children registered with the Abbottonian Medical Association Blood Care Centre, Abbottabad, in Pakistan's Khyber Pakhtunkhwa province. Electrophoretic separation of human haemoglobin like A, F, S and C was done and then haemoglobin in the gel was immobilised in a fixative solution and the gel was dried to a film. Haemoglobin pattern was visualised by staining the film with a protein-specific stain. The pattern was quantified by densitometry. RESULTS: Of the 98 samples, 57(58.2%) had b-thalassemia trait with elevated haemoglobin alpha 2 level, and 41(41.8%) had normal level. Out of the 57 carriers, 33(57.89%) were males and 24(42.10%) were females. Mean age of carriers was 11.65±6.25 years compared to 10.93±7.75 in normal patients. Mean haemoglobin alpha 2 level of carriers was 5.2±0.56% compared to 2.34±0.57% in normal subjects. CONCLUSIONS: Carrying out mass screening programmes throughout Pakistan for the detection of thalassemia carriers and providing them the benefit of marriage counselling may decrease the incidence of thalassemia Major.
Asunto(s)
Tamización de Portadores Genéticos , Pruebas Genéticas , Exámenes Prenupciales , Talasemia beta/diagnóstico , Adolescente , Niño , Preescolar , Estudios Transversales , Electroforesis , Femenino , Heterocigoto , Humanos , Lactante , Masculino , Pakistán , Adulto Joven , Talasemia beta/genética , Talasemia beta/prevención & controlRESUMEN
AIM: The aim of this study was to evaluate the effectiveness of prenatal diagnosis (PND) for the prevention of thalassemia in Southern Iran. METHODS: From 2004 to 2012 1346 couples with ß-thalassemia minor were referred to our center. Mutation analyses utilized different methods including polymerase chain reaction-based technique of amplification refractory mutation system (ARMS), Restriction Fragment Length Polymorphism Analysis of PCR-Amplified Fragments (PCR-RFLP) and Gel Electrophoresis and direct sequencing. Haplotype analysis of the ß-globin gene cluster was done routinely using the PCR-RFLP technique. RESULTS: Of the 1346 couples, 884 (66%) requested PND. They had a total of 985 pregnancies (954 singleton and 31 twin pregnancies): the 1016 fetuses underwent chorionic villus sampling (CVS). Thalassemia major was diagnosed in 266 cases (26.2%), and termination of pregnancy was requested by the parents in 264 of them (99%). Thalassemia trait was detected in 499 (49.1%) and 251 cases (24.7%) showed no ß-thalassemia mutations. There were three misdiagnoses (0.4%) (affected children diagnosed as carriers at PND). A unique pattern of thalassemia mutations was present in the study population, with IVS II-I (GâA), C36-37(-T), IVS I-5(G>C), -25bpdel (252-276), IVS I-110(G>A) and C44 (-C) being present in 62% of cases. CONCLUSION: The pattern of distribution of thalassemia mutations differs among ethnic groups within the same country.
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Diagnóstico Prenatal , Talasemia beta/prevención & control , Estudios de Cohortes , Análisis Mutacional de ADN , Femenino , Haplotipos , Humanos , Irán , Masculino , Talasemia beta/genéticaRESUMEN
Thalassemia is the most prevalent genetic blood disorder worldwide, and particularly prevalent in Indonesia. The purpose of this study was to determine the spectrum of ß-thalassemia (ß-thal) mutations found in the southern region of Central Java, Indonesia. The subjects of the study included 209 ß-thal Javanese patients from Banyumas Residency, a southwest region of Central Java Province. DNA analysis was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), amplification refractory mutation system (ARMS), and the direct sequencing method. The results showed that 14 alleles were found in the following order: IVS-I-5 (G > C) (HBB: c.92 + 5G > C) 43.5%, codon 26 (Hb E; HBB: c.79G > A) 28.2%, IVS-I-1 (G > A) (HBB: c.92 + 1G > A) 5.0%, codon 15 (TGG > TAG) (HBB: c.47G > A) 3.8%, IVS-I-1 (G > T) (HBB: c.92 + 1G > T) 3.1%, codon 35 (-C) (HBB: c.110delC) 2.4%. The rest, including codons 41/42 (-TTCT) (HBB: c.126_129delCTTT), codons 8/9 (+G) (HBB: c.27_28insG), codon 19 (AAC > AGC) (HBB: c.59A > G), codon 17 (AAG > TAG) (HBB: c.52A > T), IVS-I-2 (T > C) (HBB: c.92 + 2T > C), codons 123/124/125 (-ACCCCACC) (HBB: c.370_378delACCCCACCA), codon 40 (-G) (HBB: c.123delG) and Cap +1 (A > C) (HBB: c.-50A > C), accounted for up to 1.0% each. The most prevalent alleles would be recommended to be used as part of ß-thal screening for the Javanese, one of the major ethnic groups in the country.
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Mutación , Globinas beta/genética , Talasemia beta/epidemiología , Talasemia beta/genética , Adolescente , Adulto , Anciano , Alelos , Niño , Preescolar , Codón , Análisis Mutacional de ADN , Femenino , Genotipo , Humanos , Indonesia/epidemiología , Lactante , Intrones , Masculino , Persona de Mediana Edad , Prevalencia , Adulto Joven , Talasemia beta/prevención & controlRESUMEN
INTRODUCTION: Thalassemia is the most common genetic disorder and rising in the world as a health problem. Due to the criticality of this disease, in our country thalassemia prevention programs are more importance. The aim of this study was investigation of knowledge, attitude and behavior of marrying partners who were thalassemia genetic carriers in prevention of the birth of the children with major thalassemia. METHODS: This study was a descriptive-analytic study. Data collection tool was a self-administered questionnaire that included 43 items. The content validity of questionnaire was investigated under the supervision of physicians, experts of health education and promotion. Its reliability was confirmed by Cronbach's Alpha test. The subjects in the study consisted of 100 marrying partners who were genetic carriers of thalassemia who referred to Premarital Counseling Center in Iranshahr City. Iranshahr is a a large city of Sistan and Balouchestan Province that located in southeast of Iran. The subjects were selected by convenience non-probability sampling method. Data analyzed using descriptive and analytic statistical tests in SPSS 16.00 and level of significance considered on α<0.05. FINDINGS: The average age of men and women that participated in this study was 21.92 and 24 years respectively. 88% of the partners had familial relationships. The educational level of most of the men (34%) was diploma and of women (44%) was pre-diploma. The research findings showed that 7% and 62% of the subjects had poor and mediocre levels of knowledge respectively. Also results showed that only 13% of them had a satisfactory behavior and educational status had a positive correlation with knowledge, behavior, perceived susceptibility and perceived severity (P<0.05). As well there was a significant statistical relationship between gender and familial relationship, and the perceived barriers of participants. (p=0.01). The survey viewpoint of participants showed that they believed knowledge increasing (40%), genetic counseling (33%) and premarital screening (27%) were the most important strategies for prevention of thalassemia. CONCLUSION: The perceived barriers were the strongest predictors for preventive behaviors of incidence of major thalassemia in marrying partners, therefor educational interventions should focused on perceived barriers removing in Volunteer marrying partners.
Asunto(s)
Predisposición Genética a la Enfermedad , Conocimientos, Actitudes y Práctica en Salud , Heterocigoto , Esposos/psicología , Talasemia beta/prevención & control , Femenino , Humanos , Masculino , Medicina Preventiva , Encuestas y Cuestionarios , Talasemia beta/genéticaRESUMEN
BACKGROUND: ß-Thalassaemia is a common genetic blood disorder in the Middle Eastern region. Mandatory premarital screening and genetic counselling (PMSGC) programmes are implemented in 8 Middle East countries to reduce at-risk marriages and thus disease prevalence. A scoping review was conducted to explore the effectiveness of these programmes. METHODS: The 6-stage scoping framework of Arksey and O'Malley [Int J Soc Res Methodol 2005;8:19-32] was used. Reported outcomes were analysed per country, with success defined as achieving a 65% reduction in at-risk marriages and/or thalassaemia-affected births. Emergent enablers and barriers were analysed thematically. RESULTS: Twenty-one sources were included from the 1,348 identified, discussing 7 country programmes, with 95% (20/21) published during 2003-2013. Five publications each were included for Iran and Saudi Arabia, 3 for Turkey, 2 each for Bahrain and Iraq (Kurdistan), and 1 for the United Arab Emirates, plus 2 multi-country evaluations. No programme achieved a 65% at-risk marriage cancellation rate. Though data on thalassaemia-affected birth reductions were minimal, programmes in Iran, Turkey and Iraq reported at least 65% reductions. A thematic analysis found that screening timing, access to prenatal detection and abortion, socio-religious issues, awareness and counselling affected decisions. CONCLUSION: This review found that PMSGC programmes were unsuccessful in discouraging at-risk marriages but successful in reducing the prevalence of affected births in countries providing prenatal detection and therapeutic abortion. A life cycle approach to prevention, incorporation of school screening, awareness campaigns, reconsideration of therapeutic abortion, and screening and counselling of couples married prior to programme inception are likely to improve the effectiveness of such programmes in the Middle Eastern region.
Asunto(s)
Asesoramiento Genético/estadística & datos numéricos , Pruebas Genéticas/estadística & datos numéricos , Educación en Salud/métodos , Matrimonio/estadística & datos numéricos , Evaluación de Programas y Proyectos de Salud , Talasemia beta/epidemiología , Talasemia beta/prevención & control , Aborto Terapéutico/estadística & datos numéricos , Composición Familiar , Femenino , Predisposición Genética a la Enfermedad/genética , Humanos , Masculino , Región Mediterránea/epidemiología , Medio Oriente/epidemiología , Embarazo , Diagnóstico Prenatal/estadística & datos numéricos , Educación Prenatal/métodos , Prevalencia , Medición de Riesgo , Talasemia beta/genéticaAsunto(s)
Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/prevención & control , Antidrepanocíticos/administración & dosificación , Vacunación/métodos , Talasemia beta/prevención & control , Anemia de Células Falciformes/epidemiología , Antibacterianos/administración & dosificación , Conocimientos, Actitudes y Práctica en Salud , Humanos , Recién Nacido , Tamizaje Neonatal/organización & administración , Talasemia beta/epidemiologíaRESUMEN
BACKGROUND: The embryonic genome, including genotypes and haplotypes, contains all the information for preimplantation genetic diagnosis, representing great potential for mendelian disorder carriers to conceive healthy babies. METHODS: We developed a strategy to obtain the full embryonic genome for a ß-thalassemia-carrier couple to have a healthy second baby. We carried out sequencing for single blastomere cells and the family trio and further developed the analysis pipeline, including recovery of the missing alleles, removal of the majority of errors, and phasing of the embryonic genome. RESULTS: The final accuracy for homozygous and heterozygous single-nucleotide polymorphisms reached 99.62% and 98.39%, respectively. The aneuploidies of embryos were detected as well. Based on the comprehensive embryonic genome, we effectively performed whole-genome mendelian disorder diagnosis and human leukocyte antigen matching tests. CONCLUSIONS: This retrospective study in a ß-thalassemia family demonstrates a method for embryo genome recovery through single-cell sequencing, which permits detection of genetic variations in preimplantation genetic diagnosis. It shows the potential of single-cell sequencing technology in preimplantation genetic diagnosis clinical practices.
Asunto(s)
ADN/genética , Polimorfismo de Nucleótido Simple/genética , Diagnóstico Preimplantación/métodos , Análisis de Secuencia de ADN/métodos , Globinas beta/genética , Talasemia beta/genética , Adulto , ADN/química , Femenino , Antígenos HLA/genética , Haplotipos/genética , Humanos , Recién Nacido , Masculino , Repeticiones de Microsatélite/genética , Embarazo , Estudios Retrospectivos , Talasemia beta/prevención & controlRESUMEN
BACKGROUND AND PURPOSE: Patients with ß-thalassemia require blood transfusion to prolong their survival, which could cause iron overload in multiple organs, including the heart, liver, and brain. In this study, we aimed to quantify iron loading in the brains of patients with ß-thalassemia major through the use of MR quantitative susceptibility imaging. MATERIALS AND METHODS: Thirty-one patients with thalassemia with a mean (± standard deviation) age of 25.3 (±5.9) years and 33 age-matched healthy volunteers were recruited and underwent MR imaging at 3T. Quantitative susceptibility images were reconstructed from a 3D gradient-echo sequence. Susceptibility values were measured in the caudate nucleus, putamen, globus pallidus, red nucleus, substantia nigra, dentate nucleus, and choroid plexus. General linear model analyses were performed to compare susceptibility values of different ROIs between the patients with thalassemia and healthy volunteers. RESULTS: Of the 31 patients, 27 (87.1%) had abnormal iron deposition in one of the ROIs examined. Significant positive age effect on susceptibility value was found in the putamen, dentate nucleus, substantia nigra, and red nucleus (P = .002, P = .017, P = .044, and P = .014, respectively) in the control subjects. Compared with healthy control subjects, patients with thalassemia showed significantly lower susceptibility value in the globus pallidus (P < .001) and substantia nigra (P = .003) and significantly higher susceptibility value in the red nucleus (P = .021) and choroid plexus (P < .001). CONCLUSIONS: A wide range of abnormal susceptibility values, indicating iron overloading or low iron content, was found in patients with thalassemia. MR susceptibility imaging is a sensitive method for quantifying iron concentration in the brain and can be used as a potentially valuable tool for brain iron assessment.