TWO-STAGE ENRICHMENT OF CELLLESS EMBRYONAL DNA IN MOTHER'S PLASMA

摘要

1. A method for enriching embryonic nucleic acid, comprising the steps of! - process the biological sample of the parent organism, the "host", including cell-free embryonic nucleic acid with a composition comprising an agent with DNase activity! - where the first percentage of embryonic nucleic acid in the biological sample before processing is lower than the second percentage of embryonic nucleic acid in the biological sample after processing. ! 2. The method according to claim 1, where the biological sample is a blood sample of the parent host. ! 3. The method according to claim 1, where the biological sample is a plasma or serum sample of the parent host. ! 4. The method according to claim 1, where the agent with DNase activity is a DNase. ! 5. The method according to claim 1, where the agent with DNase activity is a DNase, and the amount of DNase is from about 10 to 200 u / μl. ! 6. The method according to claim 1, where the second percentage ratio is from about 10% to 50%. ! 7. The method according to claim 1, where the second percentage is at least 10%, 20%, 30%, 40% or 50%. ! 8. The method according to claim 1, where the first percentage of maternal nucleic acid in a biological sample before processing is higher than the second percentage of maternal nucleic acid in a biological sample after processing. ! 9. The method according to claim 1, further comprising the step of amplifying the embryonic nucleic acid in the biological sample after treatment. ! 10. The method according to claim 1, further comprising the step of amplifying the embryonic nucleic acid