A method to determine braf mutations and wild type braf protein by mass spectrometry

摘要

The invention discloses a method for determining the molar ratio between wild type (WT) BRAF protein and protein variants thereof in a biological sample, comprising the steps of: a) Digesting said sample by using a serine proteinase which specifically cleaves peptide bonds C-terminal to glutamic acid residues or peptide bonds C-terminal to glutamic or aspartic acid residues, to obtain a composition comprising a peptide fragment resulting from digestion of the peptides by the proteinase, wherein the mass of said fragment differs between said wild type (WT) B-raf protein and one said BRAF protein variant. b) Quantitatively assaying the molar amount of the peptide fragment resulting from digestion of wild type (WT) B-raf protein and the molar amount of the peptide fragment resulting from digestion of variants of the wild type (WT) B-raf protein using a mass spectrometry technique. And, c) based on the quantitative assessment calculating the at least one specific ratio between said WT BRAF protein and said variants thereof. Further, a method for estimating a subject's susceptibility to a given drug treatment for a BRAF related disease. Also, a method of treatment for a subject with a BRAF related disease.