| abstract |
Disclosed are methods and compositions for enriching nucleic acid fragments from a sample that include one or more target region of interest. In certain aspects, a sample of double stranded nucleic acid fragments having a strand-linking adapter at one end and a non- strand-linking adapter at the other end are denatured and contacted with capture probes specific for a target sequence of interest. Capture probe-bound fragments are isolated from the sample, e.g., using a solid substrate specific for the binding moiety on the capture probes, and are renatured for downstream processing, thus maintaining the original double-stranded region. This enrichment process does not require amplification and as such maintains the nucleic acids in their native states. The disclosed enrichment process and compositions are suitable for analyzing nucleic acids that are fragmented and/or damaged, e.g., cell-free DNA such as circulating tumor DNA, as well as nucleic acids that are many kilobases in length. |