Transposon nucleic acids comprising a transposon end sequence and a calibration sequence for DNA sequencing in the transposon end sequence. In one embodiment, the transposon end sequence is a Mu transposon end. A method for the generation of DNA fragmentation library based on a transposition reaction in the presence of a transposon end with the calibration sequence providing facilitated downstream handling of the produced DNA fragments, e.g., in the generation of sequencing templates.

Methods are provided for multiplexed amplification of selected targets and analysis of the amplified targets. In preferred aspects the amplification and analysis take place on the same solid support and preferably in a localized area such as a bead or a feature of an array. In preferred aspects the analysis is a determination of sequence at one or more locations in the amplified target. The methods may be used for genotyping, sequencing and analysis of copy number.

Methods are provided for multiplexed amplification of selected targets and analysis of the amplified targets. In preferred aspects the amplification and analysis take place on the same solid support and preferably in a localized area such as a bead or a feature of an array. In preferred aspects the analysis is a determination of sequence at one or more locations in the amplified target. The methods may be used for genotyping, sequencing and analysis of copy number.

Provided is a method of constructing a sequencing library. The method includes 1) providing a single-stranded DNA fragment from a biological sample; 2) subjecting the single-stranded DNA fragment to whole genomic amplification to obtain a whole genome amplification product; 3) fragmenting the whole genome amplification product using a transposase embedded with two adaptors to obtain a fragmented product with two adaptors respectively at two ends; and 4) amplifying the fragmented product with two adaptors respectively at two ends using a tag sequence and a pair of primers to obtain said sequencing library.

Disclosed is an adaptor for sequencing DNAs at ultratrace levels and its uses. The adaptor contains, from 5′terminus to 3′terminus, a Tag sequence, PolyNs, a first stem sequencing, a first loop sequence, dUTP(s), a second loop sequence, and a second stem sequence, wherein the second stem sequence is complementary to the first stem sequence when read in opposite directions, and the 5′terminus of the adaptor is phosphorylated. The adaptor is designed to form a hairpin structure itself in use and then ligated to a DNA molecule of interest, so that adaptor-adaptor ligation can be effectively avoided, eliminating the inefficient adaptor-DNA ligation problem. Such an adaptor is especially suitable for library construction and sequencing of DNAs at ultratrace levels, laying a good basis for accurate sequencing of ctDNAs.

Disclosed is an adaptor for sequencing DNAs at ultratrace levels and its uses. The adaptor contains, from 5′terminus to 3′terminus, a Tag sequence, PolyNs, a first stem sequencing, a first loop sequence, dUTP(s), a second loop sequence, and a second stem sequence, wherein the second stem sequence is complementary to the first stem sequence when read in opposite directions, and the 5′terminus of the adaptor is phosphorylated. The adaptor is designed to form a hairpin structure itself in use and then ligated to a DNA molecule of interest, so that adaptor-adaptor ligation can be effectively avoided, eliminating the inefficient adaptor-DNA ligation problem. Such an adaptor is especially suitable for library construction and sequencing of DNAs at ultratrace levels, laying a good basis for accurate sequencing of ctDNAs.

Described herein are molecules for editing a cell. The molecules described herein generally comprise the following covalently-linked components and a nucleic acid encoding a guide RNA (gRNA) sequence targeting a target region in a cell and a region homologous to the target region comprising a change in sequence relative to the target region.

The present invention relates to a method of preparing a gene cluster construct including a plurality of genes encoding a multi-modular biosynthetic enzyme, the method including (A) a step of preparing a plurality of DNA fragments which are capable of reconstructing the gene cluster construct and have structures that can be ligated to each other and (B) a step of ligating the plurality of DNA fragments prepared in the step (A) to each other by mixing the plurality of DNA fragments in a solution to obtain the gene cluster construct.

Methods and compositions for modulation of the activity of alpha thalassemia/mental retardation syndrome X-linked (ATRX), e.g., modulation of DNA-ATRX or RNA-ATRX interactions, and methods for identifying and using compounds that modulate DNA-ATRX or RNA-ATRX interactions, as well as the compounds themselves.

Methods and compositions for modulation of the activity of alpha thalassemia/mental retardation syndrome X-linked (ATRX), e.g., modulation of DNA-ATRX or RNA-ATRX interactions, and methods for identifying and using compounds that modulate DNA-ATRX or RNA-ATRX interactions, as well as the compounds themselves.