β‐Thalassaemia intermedia in Lebanon

Qatanani, Mohammed; Taher, Ali T.; Koussa, Suzanne; Naaman, Rouba Khalil; Fisher, Christopher A.; Rugless, Michelle; Old, John; Zahed, Laïla

doi:10.1034/j.1600-0609.2000.90087.x

Cited by 22 publications

(21 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This is to a considerable extent comparable with studies from some Mediterranean countries like Lebanon and Italy, where the inheritance of mild β + alleles is responsible for the majority of their TI cases [7, 15]. Another frequently encountered contributor was Xmn I polymorphism which was seen in 19/20 families (95%) with β ο / β ο and in 9/13 (69.2%) with β ο / β + but in none (0%) of those with β + / β + or those with β ο /wild genotypes (Table 2).…”

Section: Discussionsupporting

confidence: 88%

“…This is consistent with the findings of Verma and coworkers (2007) who demonstrated a similar pattern among 325 TI patients from different ethnic backgrounds in the Mediterranean region and Asia and concluded that this polymorphism is the commonest ameliorating factor in cases with β 0 mutations but not β + [16]. Accordingly in neighboring Iran, where β 0 mutations are more frequent than β + in TI patients, Xmn I polymorphism was reported as the most frequent ameliorating factor [17], while the latter polymorphism comes second in importance in the Lebanese and the Italians [7, 15], and it is almost irrelevant among Cypriots TI where β + mutations predominate [16]. The Xmn I polymorphism is one of three major Hb F quantitative trait loci (QTLs) responsible for Hb F variation, and it leads to a less severe phenotype by increasing γ chain production, which helps to neutralize unbound α -chains [18, 19].…”

Section: Discussionmentioning

confidence: 99%

“…The criteria for diagnosis were based on those proposed by Qatanani and coworkers (2000), namely, first transfusion at/or after 2 years of age and/or absence of regular transfusion dependency. The distinction between thalassemia intermedia and minor was based on the presence of mild to severe anaemia with at least one of the following: (a) transfusion at some time during life; (b) splenomegaly or splenectomy; and (c) hemoglobin electrophoresis incompatible with thalassemia minor [7]. …”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

β-Thalassemia Intermedia in Northern Iraq: A Single Center Experience

Al-Allawi

Jalal

Mohammad

et al. 2014

BioMed Research International

View full text Add to dashboard Cite

To investigate the molecular basis of β-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 β-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 β-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 β-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.

show abstract

Section: Discussionsupporting

confidence: 88%

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

β-Thalassemia Intermedia in Northern Iraq: A Single Center Experience

Al-Allawi

Jalal

Mohammad

et al. 2014

BioMed Research International

View full text Add to dashboard Cite

show abstract

“…Correlation was carried out between the XmnI [+] category and the six common mutations individually, which showed that 68% of chromosomes in the XmnI [+] category had the FSC 8 (−AA) mutation ( Table 2). The results reported here show that there is a positive correlation between the FSC 8 mutation and the −158 (C→T) polymorphism of the G γ-globin gene (p <10 −5 ) which had been previously reported in different populations (18,19).…”

Section: Xmni G G Polymorphismsupporting

confidence: 55%

Genotypic Correlation Between Six Common β-Thalassemia Mutations and theXmnI Polymorphism in the Moroccan Population

Agouti¹,

Badens

Abouyoub

et al. 2007

Hemoglobin

View full text Add to dashboard Cite

beta-Thalassemia (thal) is the most common recessive inherited disorder in Mediterranean populations. It is estimated that the frequency of this disease in the Moroccan population is between 1.5 and 3.0%. Severe forms of homozygous thalassemia cases require expensive and technically demanding curative (bone marrow transplantation) or palliative (chronic transfusion/chelation) therapies. The -158 (C-->T) polymorphism of the (G)gamma-globin gene (XmnI polymorphism) is known to ameliorate the severity of the disease because of it strong association with an increased production of fetal hemoglobin (Hb F). Among the many known mutations in Morocco, six are common [codon 39 (C-->T), frameshift codon (FSC) 8 (-AA), IVS-II-745 (CG), FSC 6 (-A), -29 (A-->G) and IVS-I-1 (G-->A)]. In this study, we have investigated, in 82 Moroccan beta-thalassemic chromosomes, the correlation between the six common mutations and the XmnI polymorphism using the Fisher exact test. The XmnI polymorphism was divided into two categories, (XmnI [+] and XmnI [-]) and the six common Moroccan mutations into two groups (group I with FSC 8 and group II without FSC 8). Correlation was carried out between the XmnI [+] category and the six common mutations individually that showed that 68% of chromosomes in the XmnI [+] category had the FSC 8 (-AA) mutation. The results reported here show that there is a positive correlation between the XmnI polymorphism and FSC 8 mutation in linkage with haplotype IV [- + - + + - +] (p <10(-5)). In conclusion, molecular determination of genetic markers in early childhood will help to identify candidates for pharmacological Hb F switching by hydroxyurea (HU). In the Moroccan population, a good response to HU treatment should be suspected in cases with the -158 (C-->T) polymorphism in linkage with haplotype IV and internal beta-globin gene framework 3.

show abstract

“…Co-inheritance of two single α-globin gene deletions (-α 3.7 or -α 4.2 deletion) in β-thalassaemia major can result in a clinical phenotype of β-thalassaemia intermedia [35]. A study on β-thalassaemia intermedia patients in Lebanon showed regular blood transfusion treatments, which can result in adverse effects, were avoided with early diagnosis of thalassaemia intermedia [36]. This is paramount to avoid treatment with regular blood transfusions as this can have adverse clinical effects.…”

Section: Discussionmentioning

confidence: 99%

Alpha-Thalassaemia in Association with Beta-Thalassaemia Patients in Malaysia: A Study on the Co-Inheritance of Both Disorders

Wee

Tan

Kuldip

et al. 2008

Public Health Genomics

View full text Add to dashboard Cite

Background/Aims: Individuals with double heterozygosity for α- and β-thalassaemia and heterozygous β-thalassaemia show a similar haematological picture. Co-inheritance of α- and β-thalassaemia in both partners may result in pregnancies with either Hb Bart’s hydrops foetalis or β-thalassaemia major, or pregnancies with both disorders. Methods: The co-inheritance of α-thalassaemia in 322 β-thalassaemia carriers in Malaysia was studied. Results: The frequency of α-thalassaemia in the β-thalassaemia carriers was 12.7% (41/322), with a carrier frequency of 7.8% for the SEA deletion, 3.7% for the -α^3.7 deletion, 0.9% for Hb Constant Spring and 0.3% for the -α^4.2 deletion. Conclusion: Double heterozygosity for α- and β-thalassaemia was confirmed in 5 out of the 41 couples and the risk of the fatal condition Hb Bart’s hydrops foetalis was confirmed in two of these couples. Detection of the Southeast Asian (SEA) deletion in the Malaysian Malays in this study confirms that Hb Bart’s hydrops foetalis can occur in this ethnic group. Results of this study have provided new information on the frequency and different types of α-thalassaemia (--^SEA, -α^3.7 and -α^4.2 deletions, Hb Constant Spring) in Malaysian β-thalassaemia carriers.

show abstract

β‐Thalassaemia intermedia in Lebanon

Cited by 22 publications

References 9 publications

β-Thalassemia Intermedia in Northern Iraq: A Single Center Experience

β-Thalassemia Intermedia in Northern Iraq: A Single Center Experience

Genotypic Correlation Between Six Common β-Thalassemia Mutations and theXmnI Polymorphism in the Moroccan Population

Alpha-Thalassaemia in Association with Beta-Thalassaemia Patients in Malaysia: A Study on the Co-Inheritance of Both Disorders

Contact Info

Product

Resources

About