Differential molecular diagnostic of the hemoglobin D-los angeles [?121(GH4) Glu>Gln] mutation with surface plasmon resonance (SPR) spectroscopy

Abstract

Objective: In this study, we aimed to determine the molecular approaches used in the laboratory diagnosis of Hb D-Los Angeles and to show rapid and reliable diagnosis of the mutation by SPR (Surface Plasmon Resonance) spectroscopy based biosensor. Materials and Methods: In this study, we were investigated with heterozygote Hb D-Los Angeles [ 1(GH4) Glu>Gln] (n:5) and healthy (Hb AA, n:5) individuals. These individuals were unrelated with each other. For the determination of the Hb D-Los Angeles mutation alkaline/acid electrophoresis DE-52 microcolumn chromatography procedures were applied at the protein level. This mutation were determinated by Eco RI restriction enzyme/SNP (Single Nucleotide Polymorphism) and labelled fluorescence automated DNA sequencing methods based on PCR (Polymerase Chain Reaction) at the gene level. We were examined by using SPR spectroscopy as real-time interactions in between biotinylated PCR products and the restriction enzyme Eco RI. Results: Differences between Hb AD-Los Angeles and Hb AA samples were determined with SPR spectroscopy as the real-time. According to our results, SPR spectroscopy method can detect the changes in between Hb AA and Hb AD Los Angeles mutation. The resonance recordings have been given 400 arc second as a result of interaction HbAA PCR products with Eco RI restriction endonuclease, whereas between Eco RI enzyme and target PCR products have been given 300 arc second in the case of heterozygous Hb D Los Angeles from the binding curves. In between them, 100 arc second of the resonance difference were caused by Hb D-Los Angeles mutation. Conclusion: Molecular diagnostic methods are important tools for the identification of the abnormal hemoglobins. Since abnormal hemoglobins present some similar results with electrophoretic and chromatographic methods, precise identification method is DNA sequencing analysis. DNA sequence analysis is not used to every laboratory routinely, because of the need for an experienced user, to give long term results and to be expensive. In this regard, we have been concluded that SPR spectroscopy can be used as routine applications in short period of time and real-time detection in the model of Hb D Los Angeles. Similar approaches based on SPR can be also developed for the abnormal hemoglobins. © 2012 Düzce Medical Journal.