Abstract: Provided in the present application is a method for constructing an RNA sequencing library, a sequencing method and a kit. The construction method comprises: acquiring a single-stranded cDNA, which is a reverse transcription product of mRNA, the 3?-terminal of the single-stranded cDNA including a cDNA tag sequence; cyclizing the single-stranded cDNA to obtain a single-stranded cyclized cDNA; amplifying the single-stranded cyclized cDNA with a primer combination, which is formed by a random primer or a gene-specific primer and a cDNA tag primer, so as to obtain an amplified fragment, the cDNA tag primer being at least a part of the cDNA tag sequence; and performing fragmentation for library construction on the amplified fragment, so as to obtain an RNA sequencing library.

Abstract: Provided are a method for detecting spatial information of nucleic acids in a sample, as well as a nucleic acid array used in the method and a method for producing the nucleic acid array.

Abstract: Provided are a sequencing library and applications thereof. The provided sequencing library includes a first nucleic acid molecule and a second nucleic acid molecule. The first nucleic acid molecule carries a cell index sequence and a droplet index sequence. The second nucleic acid molecule carries an insert fragment and a cell index sequence.

Abstract: Provided in the present invention is a method for constructing single cell sequencing libraries, comprising the following steps: a) lysing a single cell to obtain a single cell lysate; b) separating the nucleus and the cytoplasm in the single cell lysate obtained in step a) to obtain a nuclear solution and a total RNA solution; and c) constructing a chromatin DNA library with the nuclear solution obtained in step b) to obtain a chromatin-accessibility sequencing library of the single cell; and constructing a transcriptome library with the total RNA solution obtained in step b) to obtain a transcriptome sequencing library of the single cell.

Abstract: A method for constructing a library of cell-free DNAs in body fluids, comprising directly acting a transposase or an endonuclease on a body fluid sample, fragmenting the cell-free DNAs within, and performing amplification to obtain a library. Also provided is a test kit using the present method for prenatal diagnosis or early detection of cancer.

Abstract: Provided in the present invention is a method for constructing a single cell sequencing library, comprising the following steps: a) lysing a single cell to obtain a single cell lysate; b) separating the nucleus and the cytoplasm in the single cell lysate obtained in step a) to obtain a nuclear solution and a total RNA solution; and c) constructing a chromatin DNA library with the nuclear solution obtained in step b) to obtain a chromatin-accessibility sequencing library of the single cell; and constructing a transcriptome library with the total RNA solution obtained in step b) to obtain a transcriptome sequencing library of the single cell.