640 results about "Free dna" patented technology

A method and system for determining one or more sources of a cell free deoxyribonucleic acid (cfDNA) test sample from a test subject. The cfDNA test sample contains a plurality of deoxyribonucleic acid (DNA) molecules with numerous CpG sites that may be methylated or unmethylated. A trained deconvolution model comprises a plurality of methylation parameters, including a methylation level at each CpG site for each source, and a function relating a sample vector as input and a source of origin prediction as output. The method generates a test sample vector comprising a site methylation metric relating to DNA molecules from the test sample that are methylated at that CpG site. The method inputs the test sample vector into the trained deconvolution model to generate a source of origin prediction indicating a predicted DNA molecule contribution of each source.

There is described herein, a method of capturing cell-free methylated DNA from a sample having less than 100 mg of cell-free DNA, comprising the steps of: subjecting the sample to library preparation to permit subsequent sequencing of the cell-free methylated DNA; adding a first amount of filler DNA to the sample, wherein at least a portion of the filler DNA is methylated; denaturing the sample; and capturing cell-free methylated DNA using a binder selective for methylated polynucleotides.

This is described herein, a method of capturing cell-free methylated DNA from a sample having less than 100 mg of cell-free DNA, comprising the steps of: subjecting the sample to library preparation to permit subsequent sequencing of the cell-free methylated DNA; adding a first amount of filler DNA to the sample, wherein at least a portion of the filler DNA is methylated; denaturing the sample; and capturing cell-free methylated DNA using a binder selective for methylated polynucleotides.

The invention provides a methylation detection combined marker based on free DNA (cfDNA) in pulmonary alveolar lavage fluid (BAL) and application of the methylation detection combined marker. The methylation combination marker optimizes methylation detection targets in early screening of lung cancer, reduces detection difficulty and cost, and has high diagnosis accuracy, sensitivity and specificity.

Methods and systems disclosed herein can improve inference of gene expression using cell-free DNA fragments. In an aspect, the present disclosure provides a computer-implemented method for inferring gene expression, the method comprising: obtaining a biological sample from a subject; extracting cell-free deoxyribonucleic acid (cfDNA) from the biological sample, wherein the cfDNA comprises a plurality of cfDNA fragments; performing a sequencing assay on the plurality of cfDNA fragments to generate a plurality of cfDNA sequencing fragments; computer processing the plurality of cfDNA sequencing fragments; and calculating, based at least in part on the computer processing, a gene expression score for a gene in a plurality of genes, wherein the gene expression score indicates a probability of expression or non-expression of the gene in the plurality of genes.

The invention discloses a screening method of a gene region set for detecting small residual focuses of ovarian cancer, the gene region set and a detection system of the gene region set, and belongs to the technical field of gene molecular diagnosis. According to the method, a preoperative blood sample, an intraoperative multipoint tumor tissue sample and postoperative daily peritoneal drainage liquid of an ovarian cancer patient on the first to sixth days are taken as detection samples, a novel ovarian cancer nuclear genome hot spot region screening method is developed, a gene region for ovarian cancer tumor DNA detection is constructed, and tumor tissue mutation information is taken as a tracing basis, so that an ovarian cancer tumor DNA detection result is obtained. The characteristics of tumor tissue specific mutation in the free DNA of the peritoneal drainage liquid are analyzed, and the purpose of detecting the free tumor DNA of the peritoneal drainage liquid is achieved. The method can be applied to the postoperative residual focus detection of the ovarian cancer patient, can sensitively and accurately evaluate the postoperative residual focus state of the patient at an early stage, and provides timely prognosis judgment basis for clinic, so as to support the adjustment of clinical decisions.

Methods and systems for targeted detection of circulating tumor DNA (ctDNA) molecules are disclosed herein. In some cases, a molecular sequencing library depleted of methylated DNA can be generated and used to detect ctDNA in a cell-free DNA sample reliably at a lower sequencing depth and lower cost than existing methods.

The invention relates to the field of noninvasive prenatal diagnosis, and particularly discloses a preeclampsia noninvasive screening method based on deep sequencing 8bp oligonucleotide double-fragment characteristics, which comprises the following steps: collecting preeclampsia and healthy pregnant woman peripheral blood samples, and extracting free DNA for high-throughput sequencing; the method comprises the following steps: extracting core 8-mer sequences' GTGCGCCC 'and' GATGGGGT 'in a long fragment of 150-200bp through bioinformatics analysis; an integrated support vector machine, K-nearest neighbor, extreme gradient lifting, a random forest and a multi-layer perceptron are combined with a logistic regression element classifier to construct a stacking model, the frequency of a core sequence is normalized, machine learning analysis is carried out, and the preeclampsia risk is predicted. According to the invention, two 8bp oligonucleotide characteristic fragments are specifically screened, and a deep learning architecture of multi-model fusion is combined, so that the limitations of low specificity and invasive detection of a traditional screening method are effectively broken through.

Methods for non-invasive cancer detection use a combination of genome-wide mutation and fragmentation features of cfDNA that facilitate cancer screening.

The present disclosure includes a method of comprising (a) obtaining cell-free DNA (cfDNA) from a sample from a subject; (b) selectively enriching subsets of the cfDNA from (a) or derivatives therefrom having one or more target regions to obtain enriched DNA, wherein the target regions are differentially methylated in cancer; (c) sequencing the enriched DNA from (b) to obtain sequence reads; and (d) partitioning a plurality of the sequence reads into two or more groups based on their methylation status and determining the fragment length distribution of the sequence reads in at least one of the groups.

Systems and method as described herein may determine and use methylation levels associated with various tissues and samples. For example, a method may include receiving sequence reads including methylation statuses at sites of cell-free DNA molecules. The method may further include aligning the sequence reads to N sets of one or more CpG sites or genes. Then, for each set of the N sets of one or more CpG sites or genes, the method may include identifying a group of sequence reads aligning to the set of one or more CpG sites or genes and determining a methylation level using the methylation statuses of the group of sequence reads.

Methods, systems, and software for estimating circulating tumor fraction are provided. A first plurality of nucleic acid sequences for a plurality of loci in genomic DNA from a solid tumor sample is obtained. A second plurality of nucleic acid sequences for a plurality of cell-free DNA fragments obtained from a liquid biopsy sample from the same subject is obtained. One or more somatic mutations is identified in the first plurality of nucleic acid sequences. A variant allele frequency (VAF) is determined for each somatic mutation based on a frequency of the respective somatic mutation in the liquid biopsy sample and a frequency of the corresponding wild type allele in the liquid biopsy sample, thereby determining a set of VAFs. An estimate of the circulating tumor fraction for the test subject is determined based on the set of VAFs for the one or more somatic mutations.

Systems and methods for determining a blood tumor mutational burden (bTMB) for a test subject are provided in which there is obtained, from a panel-enriched sequencing reaction, a plurality of nucleic acid sequences. The plurality of nucleic acid sequences comprises a corresponding sequence for each cell-free DNA fragment in a plurality of cell-free DNA fragments obtained from a liquid biopsy sample from the test subject. Each respective cell-free DNA fragment in the plurality of cell-free DNA fragments corresponds to a respective probe sequence in a plurality of probe sequences used to enrich cell-free DNA fragments in the liquid biopsy sample in the panel-enriched sequencing reaction. There is determined, using the panel-enriched sequencing reaction, that a circulating tumor fraction (ctFE) is above a threshold ctFE value. Responsive to this determination, the bTMB is calculated for the test subject from the panel-enriched sequencing reaction and reported.

Aspects of the present disclosure are directed to methods, compositions, and kits for detection and analysis of DNA and RNA cytosine methylation. Certain aspects include methods, compositions and kits useful in bisulfite sequencing of methylated nucleic acids, including methylated nucleic acids from low-input samples such as cell-free DNA and cell-free RNA. Also disclosed are methods and compositions for detection and quantification of 5-hydroxymethylcytosine in DNA.

The present disclosure includes, among other things, methods, kits, and systems for determining the status of lung cancer. In various embodiments, the present disclosure relates to the use of one or more histone modifications, chromatin accessibility, binding of one or more transcription factors, and / or DNA methylation that that are characteristic of the status of lung cancer. In some embodiments, differential modifications and / or differential accessibility are detected and quantified at one or more genomic loci of a biological sample, e.g., in cell-free DNA (cfDNA) from a liquid biopsy sample obtained or derived from a subject with lung cancer. In various embodiments a determined status is useful, e.g., in selecting treatment for and / or treating a lung cancer.

The present disclosure includes, among other things, methods, kits, and systems for determining HER2 status of cancer, e.g., a breast, gastric / gastroesophageal, colorectal, or lung cancer. In various embodiments, the present disclosure relates to the use of one or more histone modifications, chromatin accessibility, binding of one or more transcription factors, and / or DNA methylation that that are characteristic of HER2 status of cancer. In some embodiments, differential modifications and / or differential accessibility are detected and quantified at one or more genomic loci of a biological sample, e.g., in cell-free DNA (cfDNA) from a liquid biopsy sample obtained or derived from a subject with cancer. In various embodiments a determined HER2 status is useful, e.g., in selecting treatment for and / or treating a cancer, e.g., a breast, gastric / gastroesophageal, colorectal, or lung cancer.

The present disclosure provides methods for determining the status of an allograft within a transplant recipient from genotypic data measured from a mixed sample of DNA comprising DNA from both the transplant recipient and from the donor. The mixed sample of DNA may be preferentially enriched at a plurality of polymorphic loci in a way that minimizes the allelic bias, for example using massively multiplexed targeted PCR.

Described herein are methods of preparing an enriched library of nucleic acids, comprising: (a) identifying a patient-specific panel of somatic variants present in a tumor sample from a patient, (b) generating a subset panel of somatic variants from the patient-specific panel, wherein the subset of somatic variants comprises one or more of: multi -nucleotide variants, insertions and deletions, and genomic rearrangements; (c) preparing a sample of cell-free DNA (cfDNA) fragments from the patient for sequencing; and (d) selectively enriching the cfDNA for the subset of somatic variants to generate an enriched library.

Disclosed herein in some embodiments are methods, compositions, and systems for distinguishing between ulcerative colitis (UC), Crohn's disease (CD) and other Inflammatory Bowel Disorders (IBD) by sequencing cell free nucleic acids. In some embodiments, microbial cell-free nucleic acid sequencing can provide data that can determine whether UC, CD, or other IBD are asymptomatic, in remission, or active. In some embodiments, microbial cell-free nucleic acid sequencing can provide data that can determine whether an active form of UC, CD, or other IBD is mild, moderate, or severe.

The invention relates to AAV gene therapy vectors containing novel deoxyribonuclease (DNase) transgene for delivery and expression of an enzyme which has a deoxyribonuclease (DNase) activity for enhanced clearance of cell-free DNA (cfDNA) accumulated intravasculary and / or extravasculary for treatment of various diseases and conditions, including cancer and neurodegeneration.

The present disclosure provides methods and systems that utilize analysis of cell-free DNA (cfDNA) fragmentation profiles in a sample obtained from a patient, determining a ratio of short to long fragments and a fragment size distribution from the fragmentation profile and determining a divergence score based on the ratio of short to long fragments in the sample as correlated to a ratio from a sample from a healthy patient, and determining, by the machine learning model, a monitoring score for the sample based on the fragmentation score, the divergence score, and the model weights, the monitoring score being indicative of a level of a tumor-derived nucleic acid in the cfDNA of the sample to detect, monitor, diagnose, predict cancer status, determine the likelihood of the presence of cancer and administer treatment to the patient.

The present disclosure includes, among other things, methods, kits, and systems for determining ER status of cancer, e.g., a breast cancer. In various embodiments, the present disclosure relates to the use of one or more histone modifications, chromatin accessibility, binding of one or more transcription factors, and / or DNA methylation that that are characteristic of ER status of cancer. In some embodiments, differential modifications and / or differential accessibility are detected and quantified at one or more genomic loci of a biological sample, e.g., in cell-free DNA (cfDNA) from a liquid biopsy sample obtained or derived from a subject with cancer. In various embodiments a determined ER status is useful, e.g., in selecting treatment for and / or treating a cancer, e.g., a breast cancer.

The present disclosure provides a method for obtaining a cancer risk prediction marker, a cancer risk assessment method, an electronic device, and a storage medium performed by a machine. The method for obtaining a cancer risk prediction marker includes: analyzing a plurality of peripheral blood circulating cell-free DNA (cfDNA) fragments of a biological sample of a subject to obtain sequence reads; obtaining data of a distribution of a nucleosome, and determining a predetermined interval upstream and downstream of a nucleosome center position as a nucleosome protection region; screening sequence reads of partial cfDNA fragments whose ends are located in the nucleosome protection region from the sequence reads of the plurality of cfDNA fragments; calculating a first fragmentation feature in the sequence reads of the plurality of cfDNA fragments, and calculating a second fragmentation feature in the sequence reads of the screened partial cfDNA fragments; and calculating one or more difference values of a change level of the second fragmentation feature relative to the first fragmentation feature as a cancer risk prediction marker.

SpRYc is a grafted ScCas9++-SpRY chimeric Cas9 possessing minimal 5′-NNN-3′ PAM specificity. SpRYc comprises the N-terminus (residues 1-1119) of ScCas9++ (Sc++), including the flexible loop, followed by the region of SpRY (residues 1111-1368) spanning its PAM-interacting domain mutations. Methods of altering gene expression include use of SpRYc in complex with guide RNA in a CRISPR-Cas9 system.

Analysis of cell-free DNA (cfDNA) fragment ends in patients with cancer provide a direct link between epigenetic changes and cfDNA fragmentation for non-invasive disease detection and treatment of patients.

The invention discloses a primer for diagnosis of early pregnancy of sows. The nucleotide sequence of the primer is shown as follows: SRY-O-F: 5 '-CAGCAAAATATTCTCGCCTTGG-3', and the nucleotide sequence of the primer is shown as follows. And SRY-O-R: 5 '-CATCCTCTCTCTACGC-3', and SRY-O-R: 5 '- SRY-I-F: 5 '-ATATTCTCGCCTTGGGG-3', SRY-I-F: 5 '- And SRY-I-R is 5 '-GCTTTCGGCTTCTGTA-3', and the formula is shown in the description. Two pairs of primers with high sensitivity and strong specificity are designed through comparative analysis of pig SRY gene sequences, fetal free DNA in peripheral blood of sows is used as a template, and the specificity and sensitivity of PCR are enhanced through amplification of the two pairs of primers. Through two rounds of PCR amplification, whether the sow is pregnant or not can be detected on the 18th day of pregnancy, and the accuracy of the detection result is extremely high and reaches 100%. Compared with the prior art that the ZFY gene is used for detecting the sows on the twentieth breeding day, the method has the advantages that the detection time can be advanced to the eighteenth breeding day, and the detection accuracy is greatly improved (100% vs 10%). According to the method, powerful technical support is provided for early and accurate identification of the non-pregnant sows, reduction of non-production days and feeding cost and smooth execution of a production plan.

Systems and methods for molecular residual disease (MRD) status determination for a subject's cancer condition subject uses sequence reads from methylation sequencing of cell-free DNA fragments from the subject's liquid biopsy sample to determine their methylation patterns. From this, corresponding numbers of circulating-tumor DNA (ctDNA) fragments mapping to each of a plurality of regions of the genome of the subject's species are determined. Corresponding expected numbers of noise fragments in each region are determined based on corresponding distributions using observed sequencing depths and learned background emission rates for each region. An excess fragments per million (FPM) value, corrected by an observed CHG methylation level, is determined from the observed number of ctDNA fragments in excess of the expected number of noise fragments in each region. MRD is called when the CHG corrected excess FPM value satisfies a threshold value, and a call against MRD is made when it does not.

The invention relates to the technical field of free DNA extraction, and provides a kit and a method for extracting free DNA, the kit comprises a lysis binding solution A, first magnetic beads, a lysis binding solution B, a washing solution A, a washing solution B and an eluent, and the lysis binding solution B comprises second magnetic beads; wherein the first magnetic beads tend to adsorb large-fragment nucleic acid in the environment of the splitting combination solution A, the second magnetic beads in the splitting combination solution B fully adsorb small-fragment nucleic acid, and a magnetic bar module of an instrument or an external magnetic field in other forms is used in a matched manner to complete the purification and elution process of free DNA; the purposes of improving the distribution ratio of free DNA in a nucleic acid separation product and reducing background pollution of large-fragment nucleic acid and loss of small-fragment nucleic acid are achieved; and free DNA meeting downstream application requirements can be separated under the condition of different sample qualities.

The present disclosure provides methods for determining the status of an allograft within a transplant recipient from genotypic data measured from a mixed sample of DNA comprising DNA from both the transplant recipient and from the donor. The mixed sample of DNA may be preferentially enriched at a plurality of polymorphic loci in a way that minimizes the allelic bias, for example using massively multiplexed targeted PCR.

Fragmentation of free DNA molecules is measured and used to achieve various objectives, including determining methylation at, for example, a specific site of a DNA molecule, at a specific genomic site in a reference genome of a free DNA biological sample (e.g., plasma, serum, urine, saliva) of a subject, or in a specific region in a reference genome of a biological sample (also referred to as a sample for short). Various types of fragmentation measurements may be used, such as end motifs and cleavage patterns. Another object is to determine the proportional concentration of DNA (e.g., clinically relevant DNA) of a particular tissue type. Another object is to determine a lesion in a subject using a biological sample comprising free DNA. The free DNA may be from a pathogen (e.g., a virus) in the subject or a sample of the subject. Specific tissue types of sites / regions of hypermethylation, hypomethylation, 5hmC enrichment, and 5hmC deletion may be used.