Updated Molecular Spectrum of ß-Thalassemia Mutations in Duhok Province, Northern Iraq: Ethnic Variation and the Impact of Immigration.

Immigration impact on genetic epidemiology of thalassemia worldwide is well-recognized. Over the past decade, the Duhok Province of Northern Iraq attracted a large number of immigrants. To assess whether immigration had contributed to changes in the mutation spectrum of ß-thalassemia (ß-thal) in the region, we recruited 218 registered patients with symptomatic ß-thal. The recruited patients included 50 (22.9%) from resettled migrant families. A total of 431 ß-thal alleles were fully characterized, with 20 different thalassemia mutations, the most frequent being IVS-II-1 (G>A) (HBB: c.315 + 1G>A), IVS-I-6 (T>C) (HBB: c.92 + 6T>C), codon 5 (-CT) (HBB: c.17_18delCT), IVS-I-110 (G>A) (HBB: c.93-21G>A), codon 44 (-C) (HBB: c.135delC), codon 8 (-AA) (HBB: c.25_26delAA) and IVS-I-1 (G>A) (HBB: c.92 + 1G>A) constituting 72.8% of the total. Some differences in mutation spectrum were observed compared to earlier studies from this same province, the most notable of which were the higher frequencies of IVS-I-110 and codon 8. Interestingly, the highest proportions of alleles related to immigrants were encountered in these two allele groups. Ethnic variation was also documented, so that while Muslim Kurds had IVS-II-1, IVS-I-6, IVS-I-110, codon 5 and codon 44 as their most frequent mutations, the most frequent among Kurdish Yazidis, were codon 5, codon 44, codon 8 and IVS-I-6. These ethnic variations and changes in mutation spectrums are important and should be taken in consideration to ensure effective implementation of the thalassemia preventive program.

CYP2C19 Genotype is an Independent Predictor of Adverse Cardiovascular Outcome in Iraqi Patients on Clopidogrel After Percutaneous Coronary Intervention.

To determine the impact of CYP2C19 genotyping on the occurrence of major adverse cardiovascular events (MACE), in cohort of Iraqi patients on clopidogrel after percutaneous coronary intervention (PCI), a total of 201 Iraqi patients undergoing the latter procedure were enrolled. All enrollees had their CYP2C19 genotyped using polymerase chain reaction and reverse hybridization. Genotyping revealed that CYP2C19 *1, *17, *2, and *8 allele frequencies were, respectively, 0.604, 0.276, 0.117, and 0.0026. After the exclusion of those with 2 loss of function alleles, 186 patients were available for follow-up as long as they were on clopidogrel, or until MACE occurred, which was encountered in 8.6% after a median of 12 months. Among predictors associated with MACE was the carriage of one CYP2C19 loss of function allele {hazard ratio (HR) 8.6 [confidence interval (CI) 3.15-23.4]; P < 0.0005}, hypertension [HR 3.74 (CI 1.06-13.16); P = 0.04], reduced ventricular function [HR 3.88 (1.43-10.54); P = 0.008], and history of previous myocardial infarction [HR 4.9 (CI 1.48-11.33); P = 0.007] by univariate analysis, although only CYP2C19 genotype remained significant by multivariate analysis [HR 11.88 (CI 3.25-43.44); P < 0.0005]. The latter observation favors CYP2C19 genotype-guided antiplatelet therapy and extending the use of alternative antiplatelet drugs to those with single loss of function allele after percutaneous coronary intervention.

The genetic basis of asymptomatic codon 8 frame-shift (HBB:c25_26delAA) ß(0) -thalassaemia homozygotes.

Two 21-year old dizygotic twin men of Iraqi descent were homozygous for HBB codon 8, deletion of two nucleotides (-AA) frame-shift ß(0) -thalassaemia mutation (FSC8; HBB:c25_26delAA). Both were clinically well, had splenomegaly, and were never transfused. They had mild microcytic anaemia (Hb 120-130 g/l) and 98% of their haemoglobin was fetal haemoglobin (HbF). Both were carriers of Hph α-thalassaemia mutation. On the three major HbF quantitative trait loci (QTL), the twins were homozygous for G>A HBG2 Xmn1 site at single nucleotide polymorphism (SNP) rs7482144, homozygous for 3-bp deletion HBS1L-MYB intergenic polymorphism (HMIP) at rs66650371, and heterozygous for the A>C BCL11A intron 2 polymorphism at rs766432. These findings were compared with those found in 22 other FSC8 homozygote patients: four presented with thalassaemia intermedia phenotype, and 18 were transfusion dependent. The inheritance of homozygosity for HMIP 3-bp deletion at rs66650371 and heterozygosity for Hph α-thalassaemia mutation was found in the twins and not found in any of the other 22 patients. Further studies are needed to uncover likely additional genetic variants that could contribute to the exceptionally high HbF levels and mild phenotype in these twins.

Predictors of Red Cell Alloimmunization in Kurdish Multi Transfused Patients with Hemoglobinopathies in Iraq.

Hemoglobinopathies are significant health problems in Iraq, including its Northern Kurdistan region. One of the essential components of management of these disorders is regular lifelong blood transfusions. The latter is associated with several complications including red cell alloimmunization. No study has looked at the frequency of alloimmunization and its associations in the country. To address the latter issue, 401 multi transfused patients [311 with ß-thalassemia (ß-thal) syndrome and 90 with sickle cell disease], registered at a large thalassemia care center in Iraqi Kurdistan had their records reviewed, and their sera tested for atypical antibodies using screening and extended red cell panels. Red cell alloimmunization was detected in 18 patients (4.5%) with a total of 20 alloantibodies, while no autoantibodies were detected. The most frequent alloantibody was anti-E, followed by anti-D, anti-K, anti-C(w), anti-C, anti-c and anti-Le(a). Ethnicity was an important predictor of alloimmunization, while age at start of transfusion (>2 vs. ≤2 years) (p = 0.005), Rhesus D (RhD) negative status (p = 0.0017) and history of previous transfusion reactions (p = 0.007) showed a statistically significant higher rate of alloimmunization. However, patients' age, gender, number of units transfused, underlying diagnosis and splenectomy were not significantly associated with alloimmunization. Based on our observations, measures to reduce alloimmunization rates may include extended matching for Rhesus and Kell antigens and early initiation of blood transfusions.

The Contributions of Thrombophilic Mutations to Genetic Susceptibility to Deep Venous Thrombosis in Iraqi Patients.

BACKGROUND AND AIMS: There is a paucity of data on the contribution of various thrombophilic mutations to the development of venous thrombosis in Iraqi patients. Therefore we designed a study to assess the frequencies of known thrombophilic mutations in this population. METHODS: 100 consecutive Iraqi patients with color Doppler confirmed deep venous thrombosis of the lower extremities and 100 age- and sex-matched healthy controls were enrolled in the study. Their DNAs were tested by multiplex polymerase chain reaction (PCR) followed by reverse hybridization for factor V Leiden (FVL), the prothrombin (PT) G20210A SNP, and the MTHFR C677T SNP. The factor V A4070G mutation was assessed by restriction fragment length polymorphism-PCR. RESULTS: The prevalence of FVL was 13% in patients versus 2% in controls (odd ratios [OR] 7.3; p=0.007). Patients with recurrent thrombosis also had a significantly higher frequency of Factor V Leiden (OR 8.4, p=0.0007). The prothrombin G20210A, SNP, the factor V A4070G SNP, and the MTHFR 677 TT genotypes were present among patients at 5%, 9%, and 11%, respectively, and among controls at 2%, 6%, and 6%; none of these single mutation prevalence differences were significant. Interestingly, however, when these polymorphisms were studied in aggregate we found that 24% of patients had two or more thrombophilic alleles, compared to only 8% of the controls (OR 3.6; p=0.002). This subgroup included significantly more patients with proximal (p=0.007) and recurrent thrombosis (p=0.012), as well as younger patients (≤40 years) (p=0.026). CONCLUSION: Two or more thrombophilic alleles, as well as FVL on its own, were both significantly associated with an increased risk of venous thrombosis and recurrence in Iraqi patients. Single thrombophilic mutations on their own were not associated with an increased risk.

Molecular Basis of ß-Thalassemia Intermedia in Erbil Province of Iraqi Kurdistan.

ß-Thalassemia intermedia (ß-TI) is a clinical term describing a range of clinical phenotypes that are intermediate in severity between the carrier state and ß-thalassemia major (ß-TM). To characterize the molecular basis of ß-TI in Erbil Province, Northern Iraq, 83 unrelated patients were investigated. Detection of ß-globin gene mutations was carried out by reverse hybridization assay and direct gene sequencing. All patients were screened for the XmnI polymorphism by direct sequencing of HBG2 ((G)γ promoter gene). Detection of α-globin gene deletions and triplication was carried out using the reverse hybridization assay. Four main molecular patterns were identified in association with the ß-TI phenotype, namely: ß(+)/ß(+) (38.5%), ß(+)/ß(0) (21.6%), ß(0)/ß(0) (31.3%), and ß(0)/wild type (8.4%). IVS-I-6 (T > C) was the most frequently encountered mutation (55 alleles, 34.6%), followed by IVS-II-1 (G > A) and codon 8 (-AA); furthermore, we report for the first time from Iraq two ß(+) mutations, -87 (C > G) and 5' untranslated region (5'UTR) +22 (G > A). The XmnI polymorphism was detected in 47.0% of patients, mainly in association with the ß(0)/ß(0) genotype. The α-globin gene deletions were encountered in four cases, including one case with (- -(FIL)) double gene deletion, a report that is the first from our country. The α-globin gene triplication was detected in five of the seven heterozygous ß-thalassemia (ß-thal) patients. Similar to other Mediterranean countries, inheritance of mild ß-globin mutations was the main molecular pattern underlying ß-TI in our patients followed by the ameliorating effect of the XmnI polymorphism.

Molecular Characterization of ß-Thalassemia in Nineveh Province Illustrates the Relative Heterogeneity of Mutation Distributions in Northern Iraq.

Beta thalassemia is an important health problem in Nineveh province, a large province in Northwestern Iraq. No previous study of significance had focused on the spectrum of ß-thalassemia mutations in this part of the country. A total of 94 unrelated ß-thalassemia minor subjects from the latter province were recruited. Their carrier status was confirmed by full blood count, Hb A2 and F estimation. Thereafter their DNA was subjected to multiplex polymerase chain reaction and reverse hybridization to detect 20 ß-thalassemia mutations. A total of eleven different ß-thalassemia mutations were documented. The most frequent mutation was IVS-I-110 (G>A) documented in 34 %, followed by IVS-I-6 (T>C) in 9.6 %, IVS-I-5(G>C) in 8.5 %, codon 39 (C>T) and codon 44 (-C) in 7.4 % each, while IVS-I-1(G>A) and IVS-II-1(G>A) were encountered in 6.4 % each. Other mutations were less frequent including codon 8 (-AA), IVS-I-130 (G>C), codon 5 (-CT) and IVS-II-745(C>G). The current study revealed notable differences in the relative frequencies of several ß-thalassemia mutations in Nineveh province as compared to other parts of Northern Iraq. Such an observation may be reflective of different ethnic backgrounds and varying historical population interactions. It is believed that these findings complement those of earlier studies on ß-thalassemia mutations from the country, and are quite essential in the setting of a proposed national preventive program.

Genetic Modifiers in ß-Thalassemia Intermedia: A Study on 102 Iraqi Arab Patients.

To determine the molecular basis of ß-thalassemia intermedia (TI) and the contribution of the three hemoglobin F (HbF) quantitative trait loci (QTLs) on chromosomes 11, 2, and 6 to the milder phenotype, a total of 102 Iraqi Arab patients with TI were studied. The ß and α genotypes as well as HBG2 g. 158 C>T (rs7482144), BCL11A (rs1427407 and rs10189857), and HBS1L-MYB (rs28384513 and rs9399137) by multiplex polymerase chain reaction and reverse hybridization were studied. A total of 21 different ß-thalassemia mutations arranged in 35 different genotypes were identified. The genotypes encompassed ß(+)/ß(+) mutations in 33 cases, ß(+)/ß(0) in 17 cases, ß(0)/ß(0) in 47 cases, ß(0)/wild type in 3 and ß(0)/Hb E in 2 cases. The most common was IVS-II-1 (G>A)/IVS-II-1 (G>A), followed by IVS-I-6 (T>C)/IVS-I-6 (T>C) and IVS-I-110 (G>A)/IVS-I-110 (G>A), in 31.4%, 17.6%, and 6.9%, respectively. Alpha-thalassemia mutations were found in 15.2% of those homozygous for the ß-mutations, while α gene triplication was identified in all three heterozygotes. Of the five QTLs tested, only rs7482144 and rs10189857 were significantly associated with ß(0)/ß(0) when compared to ß(+)/ß(+), with odds ratios of 6.4 (95% confidence interval [CI] 2.9-14.0) and 3.2 (95% CI 1.2-8.6), respectively. In conclusion, this study has demonstrated that among Iraqi patients with thal intermedia, the main contributors to the milder phenotype were ß(+) alleles, XmnI polymorphism, and BCL11A (rs10189857), while other QTLs on chromosomes 2 and 6, as well as alpha-thalassemia, were not significantly relevant.

Premarital screening for hemoglobinopathies: experience of a single center in Kurdistan, Iraq.

BACKGROUND: A program for the prevention of major hemoglobinopathies was initiated in 2008 in the Kurdistan region of Iraq. This study reports on the achievements and challenges of the program. METHODS: A total of 102,554 individuals (51,277 couples) visiting a premarital center between 2008 and 2012 were screened for carrier status of hemoglobinopathies, and at-risk couples were counseled. RESULTS: A total of 223 (4.3/1,000) couples were identified and counseled as high-risk couples. Available data on 198 high-risk couples indicated that 90.4% proceeded with their marriage plans, and 15% of these married couples decided to have prenatal diagnosis (PND) in subsequent pregnancies with the identification of 8 affected fetuses; all were terminated as chosen by the parents. Thirty affected births were recorded among the high-risk couples. The premarital program managed to reduce the affected birth rate of major hemoglobinopathies by 21.1%. Of the 136 affected babies born during the study period, 77.9% were born to couples married prior to the start of the program, while 22.1% were born to couples identified as having a high risk. The main reason for not taking the option of PND was unaffordable costs. CONCLUSIONS: Financial support would have increased opting for PND by high-risk couples. Further reduction in affected birth rates could be achieved by including parallel antenatal screening programs to cover those married before the initiation of the premarital program and improving the public health education and counseling programs.

Molecular Characterization of G6PD Deficient Variants in Nineveh Province, Northwestern Iraq.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency considered to be the commonest inherited enzymopathies disorders worldwide including Iraq. Studies have addressed its prevalence and molecular characterization in several parts of the country, but no data were available from Nineveh province, northwestern-Iraq regarding molecular basis of this inherited enzymopathy. To determine the molecular basis of G6PD deficient variants in Nineveh province. A total of 61 G6PD deficient male individuals from Nineveh province were enrolled in this study. DNA from all enrolled individuals were extracted and analyzed for four deficient molecular variants using a polymerase chain reaction-restriction fragment polymorphism method. These deficient variants were G6PD-Mediterranean (563 C→T), G6PD-Chatham (1003 G→A), G6PD-A-(202 G→A) and G6PD-Cosenza (1376 G→C). Also enrolled individuals were screened for silent 1311 (C→T) mutation. It was found that 46 (75.41 %) were G6PD-Mediterranean, 1(1.64 %) were G6PD-Chatham, another 1(1.64 %) were G6PD-A-, and 13 (21.31 %) were remained uncharacterized. Also all G6PD-Mediterranean as well as one uncharacterized individuals were carriers of silent 1311 (C→T) mutation. This study documented that G6PD-Mediterranean constitute the bulk of G6PD deficient variants in this province and G6PD-Chatham and A- were encountered less frequently. Also that silent 1311 (C→T) mutation were common among G6PD-Mediterranean deficient variants individuals.

Activated protein C resistance and antiphospholipid antibodies in recurrent fetal loss: experience of a single referral center in northern iraq.

The current study was initiated to determine the prevalence of activated protein C (APC) resistance, factor V Leiden and antiphospholipid antibodies (APA) in Iraqi women with recurrent fetal loss (RFL), and evaluate the outcome of intervention in those with such states. For this purpose a total of 103 Iraqi women referred to a major teaching hospital in Northern Iraq with two or more consecutive fetal losses, as well as 100 age matched women with no history of fetal loss and at least one live birth were enrolled. After appropriate clinical evaluation, the enrolled subjects were tested for APA as well as APC resistance. Subjects who were APC resistant were further tested for factor V Leiden mutation using a polymerase chain reaction and reverse hybridization. Patients with documented APA and/or with APC resistance, were put on low dose aspirin with or without low molecular weight heparin during pregnancy, and followed for a minimum of 5 years. The results revealed that among patients' group, APA were detected in 19.4 % compared to 1.0 % of the controls (OR 23.9, p = 0.00005). On the other hand, APC resistance was documented in 9.7 % compared to 1.0 % of the controls (OR 10.6, p = 0.01). Factor V Leiden was detected in 3.9 % of patients and 1 % of the controls (p = 0.38). Among 17 patients with APA available for follow up, there were 24 pregnancies, 18 of which ended with live births (75 %). While among the ten patients who had factor V Leiden or were APC resistant non-carriers, there were 13 pregnancies, 12 ended with live births (92.3 %). In conclusion, this study has demonstrated that among the enrolled Iraqi women, APA and APCR and not factor V Leiden were significantly associated with RFL, and that treatment with aspirin (with or without low molecular weight heparin) had lead to live births in 80.6 % of pregnancies.

Response to tyrosine kinase inhibitors in chronic myeloid leukemia: experience from a west Asian developing country.

Tyrosine Kinase inhibitors (TKIs) have dramatically changed the prospects for patients with chronic myeloid leukemia (CML); however, information on CML and response to TKIs from Asia are limited, particularly from West Asia, including Iraq. To address the latter issue we evaluated and monitored a cohort of 108 Iraqi patients diagnosed as chronic phase-CML, enrolled in a government-sponsored national program. The patients were all treated initially by imatinib mesylate. Ninety-two percent of patients had a complete hematological response, 38% had a major molecular response, while 79% had a major cytogenetic response after a median follow-up of 35.7 months. The 3-year Event-Free, Progression-Free, and Overall survival rates were 79.6, 87 and 98.1%, respectively. A total of 26 patients (24.1%) were shifted to an alternative TKI (Nilotinib). After one year of therapy in seventeen of the latter patients, 24% had major molecular response. In conclusion, our results compare favorably with those reported from the West and some Asian countries, and have demonstrated the importance of molecular as well as cytogenetic monitoring, and confirmed the relative success of the national CML program in our country.

ß -thalassemia intermedia in Northern Iraq: a single center experience.

To investigate the molecular basis of ß -thalassemia intermedia in Northern Iraq and evaluate its management practices, a total of 74 patients from 51 families were enrolled. The patients were clinically and hematologically reevaluated, and had their ß-thalassemia mutations characterized, as well as the number of α-globin genes and Xmn I (G)γ-158 (C>T) polymorphism studied. Out of 14 ß-thalassemia mutations identified, the four most common were IVS-I-6 (T>C) [33.3%], IVS-II-I (G>A) [21.1%], codon 82/83(-G)[10.1%], and codon 8 (-AA) [8.1%]. The most common contributing factors to the less severe phenotype of thalassemia intermedia were found to be the inheritance of mild ß-thalassemia alleles and the Xmn I polymorphism, while concomitant α-thalassemia had a limited role. Several complications were documented including: pulmonary hypertension in 20.4%, diabetes mellitus in 1.4%, hypothyroidism in 2.9%, and heart failure in 2.7%, while no documented cases of venous thrombosis were found. Compared to their counterparts in several Mediterranean countries, it appears that our patients were much less frequently transfused and had a lower proportion of patients who were splenectomized, on iron chelation, or hydroxycarbamide therapy. Such practices require further scrutiny to ensure that a better level of care is provided and that growth retardation, skeletal changes, and other complications are prevented or reduced.

Hepatitis C virus genotypes among multiply transfused hemoglobinopathy patients from Northern Iraq.

BACKGROUND AND AIM: Owing to the scarcity of data on hepatitis C virus (HCV) genotypes in Iraq and due to their epidemiological as well as therapy implications, this study was initiated aiming at determining these genotypes in Northern Iraq. MATERIALS AND METHODS: A total of 70 HCV antibody positive multi transfused patients with hemoglobinopathies, who had detectable HCV ribonucleic acid, were recruited for genotyping using genotype-specific nested polymerase chain reaction. RESULTS: The most frequent genotype detected was genotype 4 (52.9%) followed by 3a (17.1%), 1b (12.9%) and 1a (1.4%), while mixed genotypes (4 with either 3a or 1b) were detected in 7.1%. CONCLUSION: The predominance of genotype 4 is similar to other studies from surrounding Eastern Mediterranean Arab countries and to the only earlier study from central Iraq, however the significant high proportion of 3a and scarcity of 1a, are in contrast to the latter study and may be explainable by the differing population interactions in this part of Iraq. This study complements previous studies from Eastern Mediterranean region and demonstrates relative heterogeneity of HCV genotype distribution within Iraq and should trigger further studies in other parts of the country.

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), ß-thalassaemia trait, δß-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.

The spectrum of ß-thalassemia mutations in Baghdad, Central Iraq.

While previous studies from Iraq have focused on ß-thalassemia (ß-thal) mutations in the northern part of the country, inhabited mainly by Kurds, no study of significance has looked at these mutations in central or southern Iraq, which is inhabited by the Arab majority. For the latter purpose this study was initiated and 103 ß-thal carriers from Baghdad at the center of the country were investigated using multiplex polymerase chain reaction (PCR) and reverse hybridization followed by sequencing. The results revealed that a total of 17 mutations were implicated, six of which, IVS-I-110 (G>A), IVS-II-1 (G>A), IVS-I-5 (G>C), codons 8/9 (+G), IVS-I-I (G>A) and codon 44 (-C), constituted 78.0% of the mutations characterized. Among the 17 mutations identified, six are reported for the first time from Iraq and include: IVS-I, 25 bp deletion, IVS-II-848 (C>A), -28 (A>C), IVS-I-130 (G>C), IVS-I-128 (T>G) and codons 41/42 (-TTCT). The findings of the current study clearly illustrate the genetic heterogeneity of the population of central Iraq, as demonstrated by the presence of a combination of Mediterranean, Asian Indian, Kurdish, Iranian, Egyptian, Saudi Arabian and Turkish mutations that is reflective of the historical background of this part of the country.

Epidemiological profile of common haemoglobinopathies in Arab countries.

Haemoglobinopathies including the thalassemias and sickle cell disease are known to be prevalent inherited disorders in most Arab countries with varying prevalence rates and molecular characterisation. ß-thalassemia is encountered in polymorphic frequencies in almost all Arab countries with carrier rates of 1-11 % and a varying number of mutations. The most widespread mutation in Lebanon, Egypt, Syria, Jordan, Tunisia and Algeria is the IVS-I-110 (G>A). In the Eastern Arabian Peninsula, the Asian Indian mutations (IVS-I-5 (G>C), codons 8/9 (+G) and IVS-I (-25 bp del)) are more common. The α-thalassemias are encountered in the majority of Arab countries in frequencies ranging from 1 to 58 % with the highest frequencies reported from Gulf countries. The (-α(3.7)) mutation is the most frequent followed by the non-deletional α2 polyadenylation signal mutation (AATAAA>AATAAG) and the α2 IVS1 5-bp deletion. The rates of sickle cell trait in Arab countries range from 0.3 to 30 %, with the Benin, the Arab-Indian and the Bantu haplotypes constituting the bulk of the haplotypes, leading to two major phenotypes; a mild one associated with the Arab-Indian and a severe one with the Benin and Bantu haplotypes. Public health approaches targeting prevention of haemoglobinopathies in Arab countries include newborn screening for sickle cell disease, and premarital screening for carriers of ß-thalassemia and sickle cell disease. These services are still patchy and inadequate in many Arab countries recommending the upgrade of these services with strengthening of the education and training of health care providers and raising public awareness on the feasibility of prevention and care for haemoglobinopathies.

The spectrum of α-thalassemia mutations in the Kurdish population of Northeastern Iraq.

In an attempt to determine the spectrum of α-thalassemia (α-thal) mutations in the Kurdish population of Northeastern (NE) Iraq, a total of 101 unrelated adults with unexplained hypochromia and/or microcytosis were enrolled. α-Thalasssemia mutations were characterized by gap polymerase chain reaction (gap-PCR), multiplex PCR (m-PCR) and reverse hybridization and sequencing for both α genes. A total of nine α-thal mutations were characterized including four deletional ones: -α(3.7) (rightward), - -(MED-I), -(α)(20.5), -α(4.2) (leftward) and five nondeletional ones: α(polyA1)α, αα(Adana), α(-5 nt)α, α(CS)α and α(polyA2)α. These determinants were arranged in 12 different genotypes, the most frequent of which were: -α(3.7)/αα, - -(MED-I)/αα, -α(3.7)/-α(3.7), α(polyA1)α/αα, αα(Adana)/αα and -(α)(20.5)/αα. This pattern is similar to that reported in Turkey, western (W) Iran, Cyprus and Greece, and to some extent, different from the pattern observed in the Arabian Peninsula.

Sickle cell disease in the Kurdish population of northern Iraq.

Epidemiological studies have revealed that sickle cell disease patients are clustered in two geographical areas in Iraq, one among the Arabs in the extreme south, another among the Kurdish population in the extreme north, where they constitute major health problems. However, no studies have focused on the genotypes responsible for sickle cell disease or the ß-globin gene haplotypes associated with it. For the latter purpose, a total of 103 unrelated Kurdish sickle cell disease patients were evaluated by restriction fragment length polymorphism (RFLP) for the sickle cell mutation, followed by multiplex polymerase chain reaction (PCR) and reverse hybridization for ß- and α-thalassemia (ß- and α-thal) mutations, whenever indicated. Results showed that the most common genotype was sickle cell anemia (68.0%) followed by Hb S/ß(0)-thal and Hb S/ß(+)-thal at frequencies of 24.2 and 7.8%, respectively. Eight ß-thal mutations were associated with the latter two genotypes including: IVS-II-1 (G>A), IVS-I-110 (G>A), codon 8 (-AA), codon 44 (-C), codon 22 (-7 bp), IVS-I-1 (G>A), codon 30 (G>C) and IVS-I-6 (T>C). In Hb SS patients, the -α(3.7) deletion was documented in 10.0% and was the only α-thal mutation detected. Furthermore, 5' ß-globin gene cluster haplotyping of 128 ß(S) chromosomes revealed that the most common haplotype seen in 69.5% was the Benin haplotype, followed by the Arab-Indian haplotype in 12.5%. These latter findings closely resemble reports from neighboring Turkey, Syria, Jordan, Lebanon and Mediterranean countries, suggesting a possible common origin, but are in contrast to findings from the Eastern Arabian Peninsula and Iran.