Article

Isothermal Strand-Displacement Polymerase Reaction for Visual Detection of the Southeast Asian–Type Deletion of α-Thalassemia

Authors:
  • USTC-CityU Joint Advanced Research Center
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Abstract

A rapid and reliable screening test for thalassemia carrier couples is the most effective strategy to decrease the risk of conceiving fetuses with severe thalassemia. We present an approach based on the isothermal strand-displacement polymerase reaction and the use of a lateral flow strip for the visual detection of an α-thalassemia Southeast Asian-type deletion. This assay was used to evaluate 86 clinical samples (72 cases of Southeast Asian-type deletions and 14 cases of other types of thalassemia), and the results obtained were 100% consistent with those obtained using conventional gap-PCR. The approach thus provides a simple, sensitive, rapid, and cost-effective method for the diagnosis of thalassemia genotypes.

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... Based on CSDPR and gold nanoparticles (AuNPs), we have developed a lateral low biosensor (LFB) for the visual detection of thalassemia genes [11]. This sensor is highly sensitive (the detection limit is 0.01 fM of nucleic acid), highly speciic, and easy to use. ...
... Isothermal chain-displacement polymerase reaction (ISDPR) is a process that uses an isothermal amplification process to produce a large number of products to amplify the detection signal [18]. Terminal deoxynucleotidyl transferase (TdT) is a unique DNA polymerase that can catalyzes the sequential addition of dNTPs to the 3′-OH group of oligonucleotide primers to produce specific sequences such as poly-T ssDNA [19]. ...
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References 1. Modell B, Darlison M: Global epidemiology of haemoglobin disorders and derived service indicators
References 1. Modell B, Darlison M: Global epidemiology of haemoglobin disorders and derived service indicators. Bull World Health Organ 2008, 86: 480e487
A rare Hb H disease due to the --(SEA) and 16.6 kb alpha-thalassemia-2 deletions Hydrops fetalis secondary to Bart hemoglobinopathy
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  • D Yamada
  • V Steinmiller
  • E Hsia
  • Rw Hale
Sroymora S, Jindadamrongwech S, Butthep P, Chuncharunee S: A rare Hb H disease due to the --(SEA) and 16.6 kb alpha-thalassemia-2 deletions. Hemoglobin 2012, 36:200e204 8. Nakayama R, Yamada D, Steinmiller V, Hsia E, Hale RW: Hydrops fetalis secondary to Bart hemoglobinopathy. Obstet Gynecol 1986, 67: 176e180