Genotype-phenotype correlation of HbH disease in northern Iraq.

BACKGROUND: HbH disease results from dysfunction of three, less commonly two, α-globin genes through various combinations of deletion and non-deletion mutations. Characterization of the mutations and the underlying genotypes is fundamental for proper screening and prevention of thalassaemia in any region. The aim of this study was to explore the genetic arrangements of HbH disease and to correlate the genotypes with the clinical phenotypes. METHODS: A total of 44 HbH disease patients were enrolled in this study. They were clinically and haematologically assessed. The patients were tested for 21 common α-globin gene mutations using multiplex PCR and reverse hybridization. According to the genotype, the patients were categorized into two separate sub-groups, deletion and non-deletion types HbH disease. RESULTS: Within the studied HbH disease patients, eight different α-globin gene mutations were detected in nine different genetic arrangements. The --MED and -α3.7 deletions were the two most frequently encountered mutations (37.5 and 35.2% respectively). Patients with deletion genotypes constituted 70.4%. The most common detected genotype was --MED/-α3.7 (59.1%), followed by αpoly-A1α/αpoly-A1α (13.6%). For the first time, coinheritance of two relatively mild mutations (-α3.7/ααAdana) was unpredictably detected in a 1.5 year-old child with Hb of 7.1 g/dL. CONCLUSION: The HbH disease patients' clinical characteristics were variable with no ample difference between the deletion and non-deletion types. These results can be of benefit for the screening and management of thalassaemia in this region.

Molecular spectrum of α-thalassemia mutations in Erbil province of Iraqi Kurdistan.

α-Thalassemia is a globally prevalent genetic disorder of hemoglobin (Hb) structure where the rate of α-globin chain synthesis is reduced or absent based on the underlying α-globin mutation(s). This study aimed to define the spectrum of α-globin gene mutations and assess their relative frequency within a group of α-thalassemia carriers. A total of 96 young subjects with unexplained hypochromia and microcytosis were recruited. They were referred from the premarital hemoglobinopathy screening and genetic counseling center in Erbil. All subjects were genetically tested for 21 common α-globin gene mutations using multiplex PCR and reverse hybridization. Six different α-globin gene mutations and nine different genotypes were detected in 84 carrier subjects. Their mean Hb was 12.9 (± 1.29) g/dL, of whom 49 subjects (58.3%) had a normal Hb level. The two most frequently encountered mutations were -α3.7 deletion (62.86%) and α2-5nt mutation (20%). Deletions were encountered in 71.43% of the mutated alleles. The most commonly observed genotype was -α3.7/αα (46.43%), followed by -α3.7/-α3.7 and α-5ntα/αα genotypes (10.72% each). Carriers of αpoly-A1α/αα and -α3.7/-α-5ntα genotypes showed significantly lower Hb, mean cell volume, and mean cell Hb values comparing to carriers of most other genotypes. In our population, the spectrum of α-globin mutations was confined to a limited number of mutations with deletions being mostly observed.

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.

Magnitude of Bone Disease in Transfusion-Dependent and Non-Transfusion-Dependent ß-Thalassemia Patients.

Introduction ß-Thalassemia is a common inherited disease in the northern part of Iraq. A considerable number of transfusion-dependent (TDT) and non-transfusion-dependent (NTDT) ß-thalassemia patients suffer bone problems. The objective of this study was to evaluate the degree of bone disease in the TDT and NTDT patients using a dual-energy X-ray absorptiometry (DEXA) scan. Patients and methods In this study, 53 TDT and 20 NTDT patients aged ≥10 years were enrolled. Their bone status was assessed using the DEXA scan at the lumbar spine (L1-L4) and femoral neck. The effect of physical, biochemical, and hormonal characteristics on the bone mineral density (BMD) parameters was evaluated. The value of the BMD Z-score was the measure to decide on the magnitude of bone disease. Results and discussion The mean age of the enrolled patients was 24.1 years. The BMD Z-score values were significantly lower among the TDT patients at the lumbar spine and femoral neck (BMD Z-score: -2.05 and -1.51 versus -2.29 and -0.71; p=0.044 and 0.009, respectively). The proportion of osteoporosis at the lumbar spine was significantly higher in the TDT group than in the NTDT group (69.8% versus 40%; p <0.001). The BMD Z-score correlated significantly with patient BMI and parathyroid hormone (PTH) level in both the TDT and NTDT groups. No correlation was found with age, hemoglobin (Hb), and serum levels of calcium, vitamin D, ferritin, phosphorus, and alkaline phosphatase (ALP). Conclusions Impaired bone density was encountered at high proportions in our thalassemia patients. TDT patients suffered more severe bone disease than NTDT patients.

Hb SKMC and an unprecedented γδß-thalassemia: first report from Iraq.

BACKGROUND: Thalassemias are genetic disorders of globin chain synthesis. In Iraq, ß-thalassemia is more prevalent than α-thalassemia. This study identifies two unpredicted globin gene mutations, a rare α-globin gene mutation (Hb SKMC) and a novel γδß-thalassemia deletion. METHODS: Over 2 years, the Genetics unit at PAR hospital in Erbil, northern Iraq processed 137 ß-thalassemia and 97 α-thalassemia genetic testing requests. Three symptomatic thalassemia cases with unreported genotypes were identified. Proband-1α and proband-2α had Hb H disease, while proband-1ß had severe transfusion-dependent ß-thalassemia (TDT). Molecular studies included multiplex PCR, reverse hybridization, multiplex ligation-dependent probe amplification (MLPA), and globin gene sequencing. RESULTS: The α-thalassemia probands exhibited moderate microcytic hypochromic anemia with irregular transfusions and splenomegaly. Hb H disease was confirmed by positive Hb H tests and high-performance liquid chromatography (HPLC). Molecular analysis revealed heterozygous -MED deletion in proband-1α and α2Poly-A2 mutation in proband-2α. Sequencing identified the Hb SKMC (HBA1:c.283_300+3dup) mutation in both probands. The ß-thalassemia proband showed anemia and regular transfusions. Molecular studies detected the IVS1.110 G>A mutation and a novel γδß-thalassemia deletion in compound heterozygous form. The maternal sample showed the IVS1.110 G>A mutation, and MLPA confirmed the γδß-thalassemia deletion in the paternal sample. CONCLUSION: These findings highlight the genetic diversity of thalassemias in the region and emphasize the importance of advanced molecular diagnostics in detecting rare mutations.

Disseminated intravascular coagulation in a cohort of adult acute leukemia patients: a single center experience.

OBJECTIVES: We aimed to detect the incidence of disseminated intravascular coagulation (DIC) in patients with acute leukemia (AL) and find out its association with types of AL and patients' clinical and pathological parameters. METHODS: In this prospective study, 59 newly diagnosed adults with AL were clinically examined and screened for DIC presentation time. Coagulation tests, including prothrombin time, activated partial thromboplastin time, fibrinogen level, D-dimer, antithrombin, and protein C and protein S levels were all assessed. The International Society for Thrombosis and Hemostasis scoring system was adopted to diagnose overt DIC. RESULTS: The age of the studied patients ranged from 15 to 81 years with a median of 41 years; male to female ratio was 1.1:1. acute myeloid leukemia (AML) constituted 64.4% of the total cases (38 patients). DIC was detected in 28 patients (47.5%); its incidence was higher in AML than in acute lymphoblastic leukemia (ALL) (52.6% vs. 38.1%). Overt DIC was significantly associated with bleeding manifestations, duration of symptoms, and leukocytosis ( P -values = 0.050, 0.044, and 0.003, respectively). Bleeding events were encountered in 50.8% of patients (25 AML and 5 ALL patients). Bleeding was associated significantly with leukocytosis, thrombocytopenia, and low fibrinogen level. Thrombosis was found in two patients (3.4%) at presentation. CONCLUSIONS: Overt DIC was common in patients with AL at presentation, mostly in AML. Routine testing for coagulopathy in newly diagnosed AL patients will possibly aid in improving the overall patients' survival.

Overview and outcome of Hodgkin's Lymphoma: Experience of a single developing country's oncology centre.

Hodgkin's Lymphoma (HL) reveals variable epidemiological and clinico-pathological features in different geographical locations. In this retrospective study, we aimed to assess the epidemiological and clinic-pathological features, and outcome of HL patients treated at one hemato-oncology centre in Erbil, northern Iraq. Medical records of 103 HL patients treated over more than six years were reviewed. Treatment outcome was evaluated by measuring the 5-year overall and progression-free survival rates. The median age of patients was 23 years, children up to 17 years constituted 31.1%, and male to female ratio was 1:1.05. The majority (96.1%) of patients presented with lymphadenopathy. Nodular sclerosis subtype was the mostly encountered histologic type (48.5%); about half of the patients (49.5%) had stage II disease. Relapse occurred in 20 patients; the 5-year overall survival for children was better (89%) compared to adult patients (79%). The associated risk features found to have adverse effects on the survival, however, only high LDH level and presence of B-symptoms at presentation showed significant correlation. The epidemiological and clinical characteristics of HL in our locality followed the pattern in the western world. The 5-year overall and progression-free survivals were far below the international rates, a matter which may necessitate a revision to HL treatment strategy at our centre.