Patent ID: 8029996
Filing Date: 2011-10-04
Classification: C12Q

Abstract:
1. A method for the detection of cytosine methylation at more than 10 methylation positions within a CpG island in a DNA sample comprising: a) extracting DNA from a sample, b) binding the extracted DNA to a surface, c) treating the bound DNA in such a way that cytosine is converted into a base that is different in its base pairing behavior in the DNA duplex, while 5-methylcytosine remains unchanged, d) hybridizing one oligonucleotide primer to the treated DNA, e) extending the hybridized primer by more than one nucleotide in a polymerase reaction to determine the methylation state at more than 10 methylation positions within a CpG island, wherein labeled guanine derivatives are essentially incorporated only if cytosine bases were still present in the DNA treated according to step c) and wherein the extent of the incorporation of labeled nucleotides correlates with the methylation of the CpG island in the DNA sample under investigation, f) removing the labeled nucleotides that were not incorporated in the polymerase reaction, g) determining approximately the number of labels in the fragment generated by primer extension by measuring the signal intensity emitted by these labels to determine the methylation state at more than 10 methylation positions, wherein the detection of more than 10 cytosine methylation positions within said CpG island in the DNA sample is afforded.