Molecular characterization of Hb hamilton hill (HBA2: c.388delC), a novel HBA2 variant generating a premature termination codon and truncated HBA2 chain

T. Qadah, Jill Finlayson, E. North, Reza Ghassemifar

    Research output: Contribution to journalArticle

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    Abstract

    © 2015 Informa Healthcare USA, Inc. In recent years, the identification of α-thalassemias caused by nondeletional mutations has increased significantly due to the advancement of sensitive molecular genetics tools. We report clinical and experimental data for a novel frameshift mutation caused by a single base deletion at position 388 in exon 3 of the α2-globin gene (HBA2: c.388delC; Hb Hamilton Hill), resulting in the phenotype of α-thalassemia (α-thal). Hb Hamilton Hill was identified in an adult female of unknown ethnicity investigated for unexplained microcytosis. Direct DNA sequencing of the HBA2 gene revealed a heterozygous mutation, HBA2: c.388delC, and the molecular effect of this mutation was assessed experimentally using our previously described in vitro model. The experimental analysis involved transfection of a human bladder carcinoma (5637) cell line with expression vectors carrying either HBA2-wild type (HBA2-WT) or HBA2: c.388delC followed by total RNA purification and cDNA synthesis. Both wild type and mutant gene expression was studied and compared at the transcriptional and translational levels using quantitative real time polymerase chain reaction (qReTi-PCR) and immunofluorochemistry (IFC), respectively. Our experimental data showed a significant reduction by 25.0% (p=0.04) in the transcriptional activity generated from HBA2: c.388delC compared to HBA2-WT. As a result of this base deletion, a frameshift in the open reading frame generates a premature termination codon (PTC) at codon 132 of exon 3 resulting in the formation of a truncated α-globin chain. The truncated α-globin chain, observed by the IFC technique, is most likely unstable and undergoes a rapid turnover resulting in the thalassemic phenotype.
    Original languageEnglish
    Pages (from-to)88-94
    JournalHemoglobin
    Volume39
    Issue number2
    DOIs
    Publication statusPublished - 2015

    Fingerprint

    Globins
    Nonsense Codon
    Thalassemia
    Mutation
    Exons
    Genes
    Phenotype
    Frameshift Mutation
    Polymerase chain reaction
    DNA Sequence Analysis
    Gene expression
    Codon
    Open Reading Frames
    Purification
    Transfection
    Real-Time Polymerase Chain Reaction
    Molecular Biology
    Urinary Bladder
    Complementary DNA
    Cells

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    title = "Molecular characterization of Hb hamilton hill (HBA2: c.388delC), a novel HBA2 variant generating a premature termination codon and truncated HBA2 chain",
    abstract = "{\circledC} 2015 Informa Healthcare USA, Inc. In recent years, the identification of α-thalassemias caused by nondeletional mutations has increased significantly due to the advancement of sensitive molecular genetics tools. We report clinical and experimental data for a novel frameshift mutation caused by a single base deletion at position 388 in exon 3 of the α2-globin gene (HBA2: c.388delC; Hb Hamilton Hill), resulting in the phenotype of α-thalassemia (α-thal). Hb Hamilton Hill was identified in an adult female of unknown ethnicity investigated for unexplained microcytosis. Direct DNA sequencing of the HBA2 gene revealed a heterozygous mutation, HBA2: c.388delC, and the molecular effect of this mutation was assessed experimentally using our previously described in vitro model. The experimental analysis involved transfection of a human bladder carcinoma (5637) cell line with expression vectors carrying either HBA2-wild type (HBA2-WT) or HBA2: c.388delC followed by total RNA purification and cDNA synthesis. Both wild type and mutant gene expression was studied and compared at the transcriptional and translational levels using quantitative real time polymerase chain reaction (qReTi-PCR) and immunofluorochemistry (IFC), respectively. Our experimental data showed a significant reduction by 25.0{\%} (p=0.04) in the transcriptional activity generated from HBA2: c.388delC compared to HBA2-WT. As a result of this base deletion, a frameshift in the open reading frame generates a premature termination codon (PTC) at codon 132 of exon 3 resulting in the formation of a truncated α-globin chain. The truncated α-globin chain, observed by the IFC technique, is most likely unstable and undergoes a rapid turnover resulting in the thalassemic phenotype.",
    author = "T. Qadah and Jill Finlayson and E. North and Reza Ghassemifar",
    year = "2015",
    doi = "10.3109/03630269.2015.1016958",
    language = "English",
    volume = "39",
    pages = "88--94",
    journal = "Hemoglobin",
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    }

    Molecular characterization of Hb hamilton hill (HBA2: c.388delC), a novel HBA2 variant generating a premature termination codon and truncated HBA2 chain. / Qadah, T.; Finlayson, Jill; North, E.; Ghassemifar, Reza.

    In: Hemoglobin, Vol. 39, No. 2, 2015, p. 88-94.

    Research output: Contribution to journalArticle

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    T1 - Molecular characterization of Hb hamilton hill (HBA2: c.388delC), a novel HBA2 variant generating a premature termination codon and truncated HBA2 chain

    AU - Qadah, T.

    AU - Finlayson, Jill

    AU - North, E.

    AU - Ghassemifar, Reza

    PY - 2015

    Y1 - 2015

    N2 - © 2015 Informa Healthcare USA, Inc. In recent years, the identification of α-thalassemias caused by nondeletional mutations has increased significantly due to the advancement of sensitive molecular genetics tools. We report clinical and experimental data for a novel frameshift mutation caused by a single base deletion at position 388 in exon 3 of the α2-globin gene (HBA2: c.388delC; Hb Hamilton Hill), resulting in the phenotype of α-thalassemia (α-thal). Hb Hamilton Hill was identified in an adult female of unknown ethnicity investigated for unexplained microcytosis. Direct DNA sequencing of the HBA2 gene revealed a heterozygous mutation, HBA2: c.388delC, and the molecular effect of this mutation was assessed experimentally using our previously described in vitro model. The experimental analysis involved transfection of a human bladder carcinoma (5637) cell line with expression vectors carrying either HBA2-wild type (HBA2-WT) or HBA2: c.388delC followed by total RNA purification and cDNA synthesis. Both wild type and mutant gene expression was studied and compared at the transcriptional and translational levels using quantitative real time polymerase chain reaction (qReTi-PCR) and immunofluorochemistry (IFC), respectively. Our experimental data showed a significant reduction by 25.0% (p=0.04) in the transcriptional activity generated from HBA2: c.388delC compared to HBA2-WT. As a result of this base deletion, a frameshift in the open reading frame generates a premature termination codon (PTC) at codon 132 of exon 3 resulting in the formation of a truncated α-globin chain. The truncated α-globin chain, observed by the IFC technique, is most likely unstable and undergoes a rapid turnover resulting in the thalassemic phenotype.

    AB - © 2015 Informa Healthcare USA, Inc. In recent years, the identification of α-thalassemias caused by nondeletional mutations has increased significantly due to the advancement of sensitive molecular genetics tools. We report clinical and experimental data for a novel frameshift mutation caused by a single base deletion at position 388 in exon 3 of the α2-globin gene (HBA2: c.388delC; Hb Hamilton Hill), resulting in the phenotype of α-thalassemia (α-thal). Hb Hamilton Hill was identified in an adult female of unknown ethnicity investigated for unexplained microcytosis. Direct DNA sequencing of the HBA2 gene revealed a heterozygous mutation, HBA2: c.388delC, and the molecular effect of this mutation was assessed experimentally using our previously described in vitro model. The experimental analysis involved transfection of a human bladder carcinoma (5637) cell line with expression vectors carrying either HBA2-wild type (HBA2-WT) or HBA2: c.388delC followed by total RNA purification and cDNA synthesis. Both wild type and mutant gene expression was studied and compared at the transcriptional and translational levels using quantitative real time polymerase chain reaction (qReTi-PCR) and immunofluorochemistry (IFC), respectively. Our experimental data showed a significant reduction by 25.0% (p=0.04) in the transcriptional activity generated from HBA2: c.388delC compared to HBA2-WT. As a result of this base deletion, a frameshift in the open reading frame generates a premature termination codon (PTC) at codon 132 of exon 3 resulting in the formation of a truncated α-globin chain. The truncated α-globin chain, observed by the IFC technique, is most likely unstable and undergoes a rapid turnover resulting in the thalassemic phenotype.

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    DO - 10.3109/03630269.2015.1016958

    M3 - Article

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    SP - 88

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    JO - Hemoglobin

    JF - Hemoglobin

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