α-Globin Genotypes Associated with Hb H Disease: A Report from Oman and a Review of the Literature from the Eastern Mediterranean Region.
Hemoglobin
; 44(1): 20-26, 2020 Jan.
Article
en En
| MEDLINE
| ID: mdl-32019385
ABSTRACT
α-Thalassemia (α-thal) is the most common autosomal recessive hemoglobinopathy. There is a vast diversity and geographical variability in underlying genotypes in Hb H (ß4) patients. Herein, we describe the genotypes found in the largest report of Omani Hb H patients. Moreover, we reviewed and summarized the literature published from the Eastern Mediterranean region. A retrospective review of all genetically confirmed Hb H disease patients diagnosed between 2007 and 2017 at Sultan Qaboos University Hospital, Muscat, Oman, was performed. Hematological parameters and clinical presentations were assessed. Both α-globin genes were screened for deletional and nondeletional mutations using a stepwise diagnostic strategy as described before. A total of 52 patients (27 females and 25 males) with a mean age of 20.6 years (range 0.23-80.0) were molecularly confirmed to carry Hb H disease. The patients had a hemoglobin (Hb) level of 9.3 g/dL (range 5.7-13.0) and mean corpuscular volume (MCV) of 58.4 fL (range 48.2-82.1). A total of eight genotype combinations were identified, with α2 polyadenylation signal mutation (polyA1) (AATAAA>AATAAG (αPA1α/αPA1α), often cited as αT-Saudiα/αT-Saudiα, being the most common (53.8%) followed by -α3.7/- -MED I (28.8%). Our cohort also included patients with combinations of αPA1 with other Hb variants αPA1α/αPA1α with Hb S (HBB c.20A>T) trait (n = 2), -α3.7/αPA1α (n = 2) and αcodon 19α (HBA2 c.56delG)/αPA1α (n = 1). Nondeletional Hb H disease due to the αPA1 mutation is the most common in Omanis. Molecular diagnosis is necessary for accurate confirmation of the diagnosis of α-thal, determination of underlying genotypes, follow-up and counseling.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Hemoglobina A2
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Hemoglobina H
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Hemoglobina Falciforme
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Talasemia alfa
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Globinas alfa
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Anemia Hipocrómica
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Mutación
Tipo de estudio:
Diagnostic_studies
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Observational_studies
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Prognostic_studies
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Risk_factors_studies
Límite:
Adolescent
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Adult
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Aged
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Aged80
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Child
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Child, preschool
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Female
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Humans
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Infant
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Male
País/Región como asunto:
Asia
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Europa
Idioma:
En
Año:
2020
Tipo del documento:
Article