scholarly journals Interaction of rare illegitimate recombination event and a poly A addition site mutation resulting in a severe form of alpha thalassemia

Blood ◽  
1994 ◽  
Vol 83 (11) ◽  
pp. 3356-3362 ◽  
Author(s):  
P Fortina ◽  
T Parrella ◽  
M Sartore ◽  
E Gottardi ◽  
V Gabutti ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Sequence Analysis ◽  
Recombination Event ◽  
Globin Gene ◽  
Severe Form ◽  
Illegitimate Recombination ◽  
Chain Reaction ◽  
Alpha Thalassemia ◽  
Alpha Globin ◽  
Polymerase Chain

Abstract The clinical diversity of thalassemia depends on interaction of diverse genetic defects. We have characterized a severe form of alpha thalassemia caused by coinheritance of a rare alpha-globin gene deletion and a nondeletional defect in a southern Italian family. The proband, a 7-year-old girl, exhibited an abnormal hemoglobin electrophoresis pattern with hemoglobin H and hemoglobin Barts, indicating inheritance of H and hemoglobin Barts, indicating inheritance of a severe form of alpha thalassemia. Southern blot analysis of DNA showed normal as well as aberrant alpha-globin gene fragments indicating heterozygosity for a deletional form of alpha thalassemia in the proband and her mother. The coinheritance of a nondeletional form of alpha thalassemia (alpha alpha T) was suspected because of the severity of the proband's phenotype and the presence of normal alpha-globin gene fragments in the father. Selective polymerase chain reaction of the paternal alpha 1- and alpha 2-globin genes in the proband followed by DNA sequence analysis showed an AATAAA to AATGAA mutation in the polyadenylation signal sequence of the alpha 2-globin gene. Genomic DNA mapping and sequence analysis of a unique polymerase chain reaction product generated across the deletion breakpoint of the maternal allele showed a 5,201-bp deletion extending from 870 nucleotides 5′ of the alpha 2-globin gene to nucleotide +519 in the alpha 1-globin gene. This deletion is similar to that previously suggested by blotting studies in a Greek family (Pressley et al, Nucleic Acids Res 8:4889, 1980) and removes the entire alpha 2-globin gene and a portion of the 5′ end of the alpha 1-globin gene. Sequence characterization of the resultant aberrant truncated alpha 1-globin gene from the proband showed a 27 nucleotide duplication corresponding to the 3′ end of the alpha-globin gene IVS-2 region separated by the insertion of a tetranucleotide (GGTT), suggesting that this deletion is caused by an illegitimate recombination event.

scholarly journals Interaction of rare illegitimate recombination event and a poly A addition site mutation resulting in a severe form of alpha thalassemia

Blood ◽  
1994 ◽  
Vol 83 (11) ◽  
pp. 3356-3362
Author(s):  
P Fortina ◽  
T Parrella ◽  
M Sartore ◽  
E Gottardi ◽  
V Gabutti ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Sequence Analysis ◽  
Recombination Event ◽  
Globin Gene ◽  
Severe Form ◽  
Illegitimate Recombination ◽  
Chain Reaction ◽  
Alpha Thalassemia ◽  
Alpha Globin ◽  
Polymerase Chain

The clinical diversity of thalassemia depends on interaction of diverse genetic defects. We have characterized a severe form of alpha thalassemia caused by coinheritance of a rare alpha-globin gene deletion and a nondeletional defect in a southern Italian family. The proband, a 7-year-old girl, exhibited an abnormal hemoglobin electrophoresis pattern with hemoglobin H and hemoglobin Barts, indicating inheritance of H and hemoglobin Barts, indicating inheritance of a severe form of alpha thalassemia. Southern blot analysis of DNA showed normal as well as aberrant alpha-globin gene fragments indicating heterozygosity for a deletional form of alpha thalassemia in the proband and her mother. The coinheritance of a nondeletional form of alpha thalassemia (alpha alpha T) was suspected because of the severity of the proband's phenotype and the presence of normal alpha-globin gene fragments in the father. Selective polymerase chain reaction of the paternal alpha 1- and alpha 2-globin genes in the proband followed by DNA sequence analysis showed an AATAAA to AATGAA mutation in the polyadenylation signal sequence of the alpha 2-globin gene. Genomic DNA mapping and sequence analysis of a unique polymerase chain reaction product generated across the deletion breakpoint of the maternal allele showed a 5,201-bp deletion extending from 870 nucleotides 5′ of the alpha 2-globin gene to nucleotide +519 in the alpha 1-globin gene. This deletion is similar to that previously suggested by blotting studies in a Greek family (Pressley et al, Nucleic Acids Res 8:4889, 1980) and removes the entire alpha 2-globin gene and a portion of the 5′ end of the alpha 1-globin gene. Sequence characterization of the resultant aberrant truncated alpha 1-globin gene from the proband showed a 27 nucleotide duplication corresponding to the 3′ end of the alpha-globin gene IVS-2 region separated by the insertion of a tetranucleotide (GGTT), suggesting that this deletion is caused by an illegitimate recombination event.

scholarly journals Molecular Detection of alpha Thalassemia: A Review of Prevalent Techniques

2021 ◽  
Author(s):  
Divashini Vijian ◽  
Wan Suriana Wan Ab Rahman ◽  
Kannan Thirumulu Ponnuraj ◽  
Zefarina Zulkafli ◽  
Noor Haslina Mohd Noor
Keyword(s):  
Polymerase Chain Reaction ◽  
Multiplex Polymerase Chain Reaction ◽  
Complete Blood Count ◽  
Globin Gene ◽  
Molecular Techniques ◽  
Chain Reaction ◽  
Single Tube ◽  
Advantages And Disadvantages ◽  
Alpha Thalassemia ◽  
Polymerase Chain

Alpha thalassemia (α-thalassemia) is an autosomal recessive disorder due to the reduction or absence of α globin chain production. Laboratory diagnosis of α-thalassemia requires molecular analysis for the confirmatory diagnosis. A screening test, comprising complete blood count, blood smear and hemoglobin quantification by high performance liquid chromatography and capillary electrophoresis, may not possibly detect all the thalassemia diseases. This review focused on the molecular techniques used to detect α-thalassemia, and the advantages and disadvantages of each technique were highlighted. Multiplex gap-polymerase chain reaction, single-tube multiplex polymerase chain reaction, multiplex ligation-dependent probe amplification, and loop-mediated isothermal amplification were used to detect common deletion of α-thalassemia. Furthermore, the reverse dot blot analysis and a single tube multiplex polymerase chain reaction could detect non-deletion mutation of the α-globin gene. Sanger sequencing is widely used to detect non-deletion mutations of α-thalassemia. Recently, next-generation sequencing was introduced in the diagnosis of both deletion and point mutations of α-thalassemia. Despite the advantages and disadvantages of different techniques, the routine method employed in the laboratory should be based on the facility, expertise, available equipment, and economic conditions.

scholarly journals Critical analysis: use of polymerase chain reaction to diagnose leprosy

2016 ◽  
Vol 52 (1) ◽  
pp. 163-169 ◽  
Author(s):  
Flaviane Granero Maltempe ◽  
Vanessa Pietrowski Baldin ◽  
Mariana Aparecida Lopes ◽  
Vera Lúcia Dias Siqueira ◽  
Regiane Bertin de Lima Scodro ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Globin Gene ◽  
Public Health Problem ◽  
Reference Laboratory ◽  
Chain Reaction ◽  
Molecular Biology Technique ◽  
Pcr Inhibitor ◽  
Significant Difference ◽  
Polymerase Chain ◽  
Pcr Techniques

ABSTRACT Leprosy is a neglected tropical disease and an important public health problem, especially in developing countries. It is a chronic infectious disease that is caused by Mycobacterium leprae, which has a predilection for the skin and peripheral nerves. Although it has low sensitivity, slit-skin smear (SSS) remains the conventional auxiliary laboratory technique for the clinical diagnosis of leprosy. Polymerase chain reaction (PCR) is a molecular biology technique that holds promise as a simple and sensitive diagnostic tool. In the present study, the performance of two PCR methods, using different targets, PCR-LP and PCR-P, were compared with SSS with regard to leprosy diagnosis in a reference laboratory. M. leprae DNA was extracted from 106 lymph samples of 40 patients who had clinical suspicion of leprosy. The samples were subjected to both PCR techniques and SSS. Amplification of the human b-globin gene was used as PCR inhibitor control. The specificity of both PCR techniques was 100%, and sensitivity was 0.007 and 0.015 µg/ml for PCR-LP and PCR-P, respectively. No significant difference was found between either the PCR-LP or PCR-P results and SSS results (p > 0.05). Although PCR is not yet a replacement for SSS in the diagnosis of leprosy, this technique may be used as an efficient auxiliary tool for early detection of the disease, especially in endemic regions. This strategy may also be useful in cases in which SSS results are negative (e.g., in paucibacillary patients) and cases in which skin biopsy cannot be performed.

scholarly journals Diagnosis of thalassemia using cDNA amplification of circulating erythroid cell mRNA with the polymerase chain reaction [published erratum appears in Blood 1992 Jun 15;79(12):3397]

Blood ◽  
1991 ◽  
Vol 78 (9) ◽  
pp. 2433-2437 ◽  
Author(s):  
SZ Huang ◽  
GP Rodgers ◽  
FY Zeng ◽  
YT Zeng ◽  
AN Schechter
Keyword(s):  
Polymerase Chain Reaction ◽  
Globin Gene ◽  
Erythroid Cell ◽  
Mrna Levels ◽  
Beta Globin ◽  
Chain Reaction ◽  
Globin Mrna ◽  
Gamma Globin ◽  
Polymerase Chain ◽  
Alpha Beta

Abstract We have developed a technique to diagnose the alpha- and beta- thalassemia (thal) syndromes using the polymerase chain reaction to amplify cDNA copies of circulating erythroid cell messenger RNA (mRNA) so as to quantitate the relative amounts of alpha-, beta-, and gamma- globin mRNA contained therein. Quantitation, performed by scintillation counting of 32P-dCTP incorporated into specific globin cDNA bands, showed ratios of alpha/beta-globin mRNA greater than 10-fold and greater than fivefold increased in patients with beta 0- and beta (+)- thal, respectively, as well as a relative increase in gamma-globin mRNA levels. Conversely, patients with alpha-thalassemia showed a decreased ratio of alpha/beta-globin mRNA proportional to the number of alpha- globin genes deleted. This methodology of ascertaining ratios of globin mRNA species provides a new, simplified approach toward the diagnosis of thalassemia syndromes, and may be of value in other studies of globin gene expression at the transcription level.

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