Mutation analysis using mass spectrometry

Method for the mass-spectrometric determination of known mutations in genomic DNA characterized by the following steps:

• 1) providing an amount of DNA containing the mutation,
• 2) adding primers and a set of modified non-terminating nucleotide triphosphates (NTP) and terminating nucleotide triphosphates for the method of primer extension, the modifications of the nucleotide triphosphates enabling neutralization of the primer extension product in step 5, and with charge tags either at the primers or at the terminating nucleotide triphosphates,
• 3) hybridizing the primers on a suitable DNA strand and extending the primers in an enzymatic complementary copy reaction,
• 4) decomposing or removing at least one defined part each of the primers from the extended primer product chains,
• 5) chemically neutralizing the remaining product chains except for the charge tags, using the modified sites of the nucleobases for neutralization, and
• 6) mass-spectrometrically determining the mass of the product chains and assigning the masses detected to the wild type or known mutant.