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High-throughput SNP genotyping with the Masscode system.

M Kokoris·K Dix·K Moynihan·J Mathis·B Erwin·P Grass·B Hines·A Duesterhoeft
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Abstract

QIAGEN Genomics, Inc, has developed the Masscode tagging system for DNA labeling and detection. In this application, the Masscode system is described as applied to high-throughput single-nucleotide polymorphism (SNP) genotyping. The labeling system is based on a small-molecular-weight tag that is covalently attached through a photocleavable linker to a DNA oligonucleotide. The tagged oligonucleotide is used as a primer in an allele-specific PCR SNP discrimination assay. The allele-specific amplicons are differentiated through their Masscode tag assignments. After a photolysis step to cleave the tags from the amplicon, the samples are introduced into a single quadrupole mass spectrometry detection system for analysis. Genotyping determinations are based on the relative proportions of the paired allele tags. The system has a lower limit of detection in the femtomolar range (10(-15) M). At present, 30 different Masscode tags may be used simultaneously in a multiplex fashion to routinely provide more than 40,000 SNP genotyping measurements daily. Further developments will allow for the simultaneous detection of several hundred tags.

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AllelesGene Expression ProfilingGenotypeHumansMass SpectrometryPolymorphism, Single NucleotideProteomeJournal ArticleReview

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M Kokoris, K Dix, K Moynihan, J Mathis, B Erwin, P Grass, B Hines, A Duesterhoeft. 2000. High-throughput SNP genotyping with the Masscode system.. https://doi.org/10.1007/bf03262094

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