Method for differential treatment of nucleic acid contents of a sample, sample enrichment, kit and uses thereof

摘要

The invention relates to a method and a kit for in vitro differential treatment of nucleic acid molecules contained in a biological sample and comprising a first subpopulation of free nucleic acids of higher eukaryotic cells and at least one further subpopulation of nucleic acids of microorganism(s) wherein said microorganism(s) nucleic acids are packaged nucleic acids that represents quantitatively a minor group of the nucleic acids of the sample, comprising at least the steps of:
a. exposing the biological sample to conditions enabling the modification of the 3'- and/or 5'- extremities of degraded nucleic acid molecules of the first nucleic acids subpopulation in order to impair their ligation capacity;
b. extracting nucleic acid molecules of the sample and thereby recovering degraded nucleic acid molecules of the first nucleic acids subpopulation having modified 3'- and/or 5'- extremities and nucleic acid molecules of the further subpopulation having non-modified 3'- and/or 5'- extremities.