The present disclosure relates to the field of biotechnology, in particular, to a combination product for detecting DNA. The product includes ribonuclease H II and a probe; the probe is a single-stranded probe and has a sequence which can be partially or entirely complementary to a target DNA molecule to be detected, and one or more RNA bases are embedded in the complementary region of the probe and divide the complementary region of the probe into at least two segments, each of which independently has DNA bases and base substitutions of less than or equal to 13 in total.

The present invention determines lymphocyte clonality by contacting a sample comprising nucleic acid molecules (1) of lymphocytes with forward and reverse primers (10, 20) and amplifying the nucleic acid molecules (1) by performing PCR pre-amplification to form barcoded PCR products (50). The barcoded PCR products (50) are amplified using adapter-specific forward and reverse primers (30, 40) in a PCR application into amplified barcoded PCR products (60), which are sequenced. The sequence reads are demultiplexed, mapped to respective TCR or BCR clonotypes and used to determine lymphocyte clonality for the sample. The forward and/or reverse primers (10, 20) are barcoded by comprising UMIs (14, 24) protected inside hairpin loops.

The present invention determines lymphocyte clonality by contacting a sample comprising nucleic acid molecules (1) of lymphocytes with forward and reverse primers (10, 20) and amplifying the nucleic acid molecules (1) by performing PCR pre-amplification to form barcoded PCR products (50). The barcoded PCR products (50) are amplified using adapter-specific forward and reverse primers (30, 40) in a PCR application into amplified barcoded PCR products (60), which are sequenced. The sequence reads are demultiplexed, mapped to respective TCR or BCR clonotypes and used to determine lymphocyte clonality for the sample. The forward and/or reverse primers (10, 20) are barcoded by comprising UMIs (14, 24) protected inside hairpin loops.

The present methods are exemplified by a process in which maternal blood containing fetal DNA is diluted to a nominal value of approximately 0.5 genome equivalent of DNA per reaction sample. Digital analysis is then be used to detect aneuploidy, such as the trisomy that causes Down Syndrome. Since aneuploidies do not present a mutational change in sequence, and are merely a change in the number of chromosomes, it has not been possible to detect them in a fetus without resorting to invasive techniques such as amniocentesis or chorionic villi sampling. Digital amplification allows the detection of aneuploidy using massively parallel amplification and detection methods, examining, e.g., 10,000 genome equivalents.

The present methods are exemplified by a process in which maternal blood containing fetal DNA is diluted to a nominal value of approximately 0.5 genome equivalent of DNA per reaction sample. Digital analysis is then be used to detect aneuploidy, such as the trisomy that causes Down Syndrome. Since aneuploidies do not present a mutational change in sequence, and are merely a change in the number of chromosomes, it has not been possible to detect them in a fetus without resorting to invasive techniques such as amniocentesis or chorionic villi sampling. Digital amplification allows the detection of aneuploidy using massively parallel amplification and detection methods, examining, e.g., 10,000 genome equivalents.

The invention provides methods, compositions, kits and devices for the detection of target molecules. In some embodiments, the invention allows for multiplexed target molecule detection.

The invention provides methods, compositions, kits and devices for the detection of target molecules. In some embodiments, the invention allows for multiplexed target molecule detection.

The present invention provides a method for sequencing a nucleic acid using an immersion reaction protocol. The immersion reaction protocol comprises sequentially immersing a solid support having nucleic acid molecules immobilized thereon in different reaction containers to realize nucleic acid sequencing.

The present invention provides a method for sequencing a nucleic acid using an immersion reaction protocol. The immersion reaction protocol comprises sequentially immersing a solid support having nucleic acid molecules immobilized thereon in different reaction containers to realize nucleic acid sequencing.

This invention provides ultra-sensitive methods and compositions for detecting patient-specific mutations from cell free nucleic acids (cfDNA) without sequencing. Methods of the invention make use of fluidic partitions for multiplex amplification of cfDNA and thereby create a library of uniformly amplified amplicons. The uniformly amplified amplicons can be split into any number of different detection reactions (while maintaining detection sensitivity) for single-plex detection of mutations present in cfDNA. These methods provide substantially improved signal to noise ratio and easier discrimination of low-abundance mutations.