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Quantitative approach to single-nucleotide polymorphism analysis using MALDI-TOF mass spectrometry.

P Ross·L Hall·L A Haff
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Abstract

Pooling of DNA samples before genotyping is a valuable means of streamlining large-scale genotyping efforts in disease association studies, single-nucleotide polymorphism (SNP) validation or mutant allele screening programs. In this report, we explore the application of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to quantitative analysis of SNPs. The measurements are based on MALDI-TOF MS analysis of primer extension assays performed on standard mixtures of pooled PCR products at several test loci. The inherent high molecular weight resolution of MALDI-TOF MS conveys high specificity and good signal-to-noise ratio for performing accurate quantitation. The methods described maximize the sensitivity and quantitative capacity of MALDI-TOF MS while preserving the throughput and economic advantages of the MALDI-TOF platform. Using the format described, we demonstrate that allele frequencies as low as 5% can be detected quantitatively and unambiguously.

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AllelesCytochrome P-450 Enzyme SystemDNAFructose-Bisphosphate AldolaseGene FrequencyGenotypePolymerase Chain ReactionPolymorphism, Single NucleotideReceptors, LDLSpectrometry, Mass, Matrix-Assisted Laser Desorption-IonizationJournal Article

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P Ross, L Hall, L A Haff. 2000. Quantitative approach to single-nucleotide polymorphism analysis using MALDI-TOF mass spectrometry.. https://doi.org/10.2144/00293rr05

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