Genotyping single-nucleotide polymorphisms by matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry

Centre National de Génotypage, Évry-Petit-Bourg, Île-de-France, France
Journal of Chromatography B (Impact Factor: 2.69). 01/2003; 782(1-2):73-87. DOI: 10.1016/S1570-0232(02)00692-X
Source: PubMed

ABSTRACT In recent years matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI) has emerged as a very powerful method for genotyping single nucleotide polymorphisms. The accuracy, speed of data accumulation, and data structure are the major features of MALDI. Several SNP genotyping methods have been implemented with a high degree of automation and are being applied for large-scale association studies. Most methods for SNP genotyping using MALDI mass spectrometric detection and their potential application for high-throughput are reviewed here.

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    • "The protocol includes an initial PCR amplification of the region surrounding the sequence variation of interest, followed by the addition of a primer with mass-modified terminators that anneals immediately upstream of the polymorphic site and produces a specific single-base extension of the product complementary to the SNV (Gabriel et al. 2009). The mass difference of the single-base extension products enables allelic discrimination, which is performed by MALDI-TOF mass spectrometry (Sauer and Gut, 2002). Several SNVs of interest can be amplified simultaneously, a process known as 'multiplexing'. "
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Sascha Sauer