Matrix-assisted laser desorption/ionization mass spectrometric analysis of DNA on microarrays.
BACKGROUND
Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry is a powerful tool in biomolecule analysis with a wide range of application possibilities, including genotyping of single-base variations (also known as single-nucleotide polymorphisms, or SNPs) for candidate gene studies and diagnostic typing of DNA markers. We tested a method that does not require stringent purification of the nucleic acids and/or the use of modification chemistry before mass spectrometry analysis.


METHODS
We used an alternative direct analysis approach that allows MALDI analysis of crude DNA samples printed on microscope slides densely coated with primary amino groups that efficiently bind negatively charged DNA. After simple washing of the slides, we applied MALDI matrix and used a conventional MALDI mass spectrometer to detect DNA products.


RESULTS
We analyzed crude oligonucleotide samples and performed automated genotyping of single-base variations in 72 DNA samples.


CONCLUSIONS
This procedure offers an operational short-cut compared with standard MALDI procedures for preparation of oligonucleotides, including purification, and thus is an efficient tool for genotyping applications, particularly those requiring accurate, flexible, and rapid data generation and medium throughput.
Kepper
Pamela
P
Max Planck Institute for Molecular Genetics, Department of Vertebrate Genomics, Ihnestrasse 63-73, 14195 Berlin-Dahlem, Germany.
Reinhardt
Richard
R
Dahl
Andreas
A
Lehrach
Hans
H
Sauer
Sascha
S
D000588:Amines / Q000737:chemistry; D004247:DNA / Q000032:analysis* / Q000737:chemistry; D050091:Dendrimers; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D009841:Oligonucleotides / Q000737:chemistry; D015203:Reproducibility of Results; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D000588:Amines; D050091:Dendrimers; D009841:Oligonucleotides; D004247:DNA