Patent ID: 10227646

Abstract:
A method for identifying any of the presence, location and phasing of modified cytosines (C) in long stretches of nucleic acids is provided. In some embodiments, the method may comprise (a) reacting a first portion of a nucleic acid sample containing at least one C and/or at least one modified C with a DNA glucosyltransferase and a cytidine deaminase to produce a first product and/or reacting a second portion of the sample with a dioxygenase, optionally a DNA glucosyltransferase and a cytidine deaminase to produce a second product and; (b) comparing the sequences from the first and optionally the second product obtained in (a), or amplification products thereof, with each other and/or an untreated reference sequence to determine which Cs in the initial nucleic acid fragment are modified. A modified TET methylcytosine dioxygenase with improved efficiency compared to unmodified TET2 at converting methylcytosine to carboxymethylcytosine is also provided.