Provided herein is technology relating to the amplification-based detection of bisulfite-treated DNAs and particularly, but not exclusively, to methods and compositions for multiplex amplification of low-level sample DNA prior to further characterization of the sample DNA. The technology further provides methods for isolating DNA from blood or blood product samples, e.g., plasma samples.

Method of identifying a cognate nucleotide (i.e., the “next correct nucleotide”) for a primed template nucleic acid molecule. In some embodiments, an ordered or random array of primed target nucleic acids characterized by different cognate nucleotides can be evaluated using a single imaging step to identify different cognate nucleotides for a collection of different primed template nucleic acid molecules. An optional incorporation step can follow the identifying step. A polymerase different from the ones used in the binding and examination steps can be used to incorporate a nucleotide, such as a reversible terminator nucleotide, preliminary to identification of the next cognate nucleotide.

Method of identifying a cognate nucleotide (i.e., the “next correct nucleotide”) for a primed template nucleic acid molecule. In some embodiments, an ordered or random array of primed target nucleic acids characterized by different cognate nucleotides can be evaluated using a single imaging step to identify different cognate nucleotides for a collection of different primed template nucleic acid molecules. An optional incorporation step can follow the identifying step. A polymerase different from the ones used in the binding and examination steps can be used to incorporate a nucleotide, such as a reversible terminator nucleotide, preliminary to identification of the next cognate nucleotide.

The present invention discloses a two-stage reaction and detection tube comprises a first tube, a second tube and a connector. The first tube comprises a detection space for placing a dipstick and a detection space for the test result. The second tube comprises a storing space for the PCR or RT-PCR reagents and the target gene segments. The connector comprises a first portion and a second portion which connect to the first tube and the second tube respectively. The connector further comprises a diversion unit, a liquid collection space, and a dipstick fixing space, where the liquid collection space is connected to the dipstick fixing space. The target gene amplification and detection could be directly processed in the same tube without any liquid transfer.

The present invention discloses a two-stage reaction and detection tube comprises a first tube, a second tube and a connector. The first tube comprises a detection space for placing a dipstick and a detection space for the test result. The second tube comprises a storing space for the PCR or RT-PCR reagents and the target gene segments. The connector comprises a first portion and a second portion which connect to the first tube and the second tube respectively. The connector further comprises a diversion unit, a liquid collection space, and a dipstick fixing space, where the liquid collection space is connected to the dipstick fixing space. The target gene amplification and detection could be directly processed in the same tube without any liquid transfer.

This disclosure provides, among other things, methods for generating and applying therapeutic interventions. The methods involve, for example, (a) sequencing polynucleotides from cancer cells from a subject; (b) identifying and quantifying somatic mutations in the polynucleotides; (c) developing a profile of tumor heterogeneity in the subject indicating the presence and relative quantity of a plurality of the somatic mutations in the polynucleotides, wherein different relative quantities indicates tumor heterogeneity; and (d) determining a therapeutic intervention for a cancer exhibiting the tumor heterogeneity, wherein the therapeutic intervention is effective against a cancer having the profile of tumor heterogeneity determined.

This disclosure provides, among other things, methods for generating and applying therapeutic interventions. The methods involve, for example, (a) sequencing polynucleotides from cancer cells from a subject; (b) identifying and quantifying somatic mutations in the polynucleotides; (c) developing a profile of tumor heterogeneity in the subject indicating the presence and relative quantity of a plurality of the somatic mutations in the polynucleotides, wherein different relative quantities indicates tumor heterogeneity; and (d) determining a therapeutic intervention for a cancer exhibiting the tumor heterogeneity, wherein the therapeutic intervention is effective against a cancer having the profile of tumor heterogeneity determined.

The present disclosure provides methods for determining the ploidy status of a chromosome in a gestating fetus from genotypic data measured from a sample of DNA from the mother of the fetus and from the fetus, and from genotypic data from the mother and optionally also from the father. The ploidy state is determined by using a joint distribution model to create a set of expected allele distributions for different possible fetal ploidy states given the parental genotypic data, and comparing the expected allelic distributions to the pattern of measured allelic distributions measured in the mixed sample, and choosing the ploidy state whose expected allelic distribution pattern most closely matches the observed allelic distribution pattern. In an embodiment, the mixed sample of DNA may be preferentially enriched at a plurality of polymorphic loci in a way that minimizes the allelic bias.

Methods of determining methylation of DNA are provided. In one illustrative, but non-limiting embodiment the method comprises i) contacting a biological sample comprising a nucleic acid to a first matrix material comprising a first column or filter where said matrix material binds and/or filters nucleic acids in said sample and thereby purifies the DNA; ii) eluting the bound DNA from the first matrix material and denaturing the DNA to produce eluted denatured DNA; iii) heating the eluted DNA in the presence of bisulfite ions to produce a deaminated nucleic acid; iv) contacting said deaminated nucleic acid to a second matrix material comprising a second column to bind said deaminated nucleic acid to said second matrix material; v) desulphonating the bound deaminated nucleic acid and/or simultaneously eluting and desulphonating the nucleic acid by contacting the deaminated nucleic acid with an alkaline solution to produce a bisulfite converted nucleic acid; vi) eluting said bisulfite converted nucleic acid from said second matrix material; and vii) performing methylation specific PCR and/or nucleic acid sequencing, and/or high resolution melting analysis (HRM) on said bisulfite-converted nucleic acid to determine the methylation of said nucleic acid, wherein at least steps iv) through vi) are performed in a single reaction cartridge.

Provided in some aspects are methods for light-controlled in situ surface patterning of a substrate. Compositions such as nucleic acid arrays produced by the methods are also disclosed. In some embodiments, provided herein is photocontrollable hybridization, where oligonucleotides with photo-caged bases prevent hybridization of complementary nucleic acid strands. Uncaging of the oligonucleotides allows hybridization and/or ligation of nucleic acid molecules at the exposed area. A large diversity of barcodes can be created in molecules on the substrate via sequential rounds of light exposure, hybridization, and ligation.