Journals / International Journal of Medical Biochemistry / 2021 / Cilt: 4 - Sayı: 2

Association between HBA locus copy number gains and pathogenic HBB gene variants

Pages
91–96
DOI
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

The results indicated that β-thalassemia mutations with a co-occurrence of increased α-globin gene dosage is not very rare condition.

📌 3 Key Takeaways

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Objective & Hypothesis:Objectives: Alpha (α) and beta (β) thalassemia are the most prevalent genetic hematological disorders.
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Key Findings & Data:Methods: Multiplex ligation-dependent probe amplification and Sanger sequencing were used to identify the hemo globin subunit alpha 1 (HBA1) and HBA2 gene alterations in 32 patients.
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Conclusion & Impact:The results indicated that β-thalassemia mutations with a co-occurrence of increased α-globin gene dosage is not very rare condition.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:Domain Parameters

Özet

Objectives: Alpha (α) and beta (β) thalassemia are the most prevalent genetic hematological disorders. The co-occur rence of silent β-thalassemia with excess α-globin gene copies is associated with the thalassemia intermedia pheno type. This study was an investigation of the α-globulin gene dosage and sequence variations in thalassemia patients. Methods: Multiplex ligation-dependent probe amplification and Sanger sequencing were used to identify the hemo globin subunit alpha 1 (HBA1) and HBA2 gene alterations in 32 patients. Deletion, duplication, and other findings were analyzed in the index cases and family members. Results: Four of the 32 cases (12.5%) were found to have gross duplications. Two cases demonstrated α-globin triplica tion, and 2 had a quadruplicated HBA1/2 genes. Affected family members revealed genotype-phenotype correlation. In 1 patient, it was observed that quadruplicated HBA genes co-occurrence with hemoglobin subunit beta (HBB) mu tation was inherited from his mother. Notably, the mother did not demonstrate any thalassemia phenotype. Further investigation showed that the mother was carrying a single copy HBA gene deletion in the trans allele that explained her clinical condition. Conclusion: This study examined the effect of increased copies of the HBA gene in HBB gene pathogenic variant car riers. The results indicated that β-thalassemia mutations with a co-occurrence of increased α-globin gene dosage is not very rare condition. Patients with clinical findings incompatible with their HBB genotypes should be investigated for small and gross α-globin gene variants in order to provide genetic counseling and prenatal diagnosis follow-up, as appropriate.

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Cite This Article

TOKSOY, G., AKAY, N., AGHAYEV, A., KARAMAN, V., AVCI, Ş., KALAYCI, T., ALTUNOĞLU, U., KARAKAŞ, Z., UYGUNER, Z. O. (2021). Association between HBA locus copy number gains and pathogenic HBB gene variants. International Journal of Medical Biochemistry, Cilt: 4 - Sayı: 2, 91–96. https://ajindex.com/articles/406974

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