Molecular tag connector as well as preparation method and application thereof

Abstract

The invention discloses a molecular tag connector as well as a preparation method and application thereof. According to the molecular tag connector, a nucleic acid molecule (molecular tag connector) (also named as nucleic acid molecule A) is firstly protected, which is as shown in sequence 5 or sequence 6 or sequence 7 or sequence 8 of a sequence list. The invention also protects a nucleic acid molecule mixture (also named as nucleic acid molecule A mixture) which consists of a nucleic acid molecule shown by sequence 5 of the sequence list, the nucleic acid molecule shown by sequence 6 of thesequence list, the nucleic acid molecule shown by sequence 7 of the sequence list and the nucleic acid molecule shown by sequence 8 of the sequence list. The molecular tag connector has great application and popularization value for detecting ultralow-frequency gene mutation. The mutation of the ultralow-frequency gene is generally ctDNA in total DNA of peripheral blood, so that by utilizing the molecular tag connector, the diagnosis can be more effectively assisted or the drug application can be more effectively instructed.

Description

technical field [0001] The invention belongs to the field of gene detection, and relates to a molecular tag adapter, a preparation method and application thereof, in particular to an application in ultra-low frequency gene variation detection. Background technique [0002] Next-generation sequencing (NGS), also known as high-throughput sequencing, can sequence hundreds of thousands to millions of DNA molecules at a time, and can simultaneously obtain billions of DNA in a specific sample Base sequence information is an efficient means of discovering known and unknown gene variations. [0003] Due to DNA oxidative damage or deamination damage, mutations introduced by DNA polymerase in PCR amplification (the probability of error for each base is within 10 -6 ~10 -4 between), especially the errors introduced in the first round of amplification and the errors introduced by the sequencing instrument when reading bases, the error probability of each base obtained by sequencing is...

AI Technical Summary

Problems solved by technology

[0005] At present, there are already library-building sequencing methods for the detection of ultra-low-frequency gene variations, which mainly introduce molecular tag sequences unique identifiers (UIDs), that is, molecular barcodes, at both ends of the original double-stranded DNA molecular template, but there are still many limitations in practical applications sex

The first method is called Duplex Sequencing, which is to introduce UID into the Y-shaped adapter, and use single-strand consensus sequences (SSCSs) and duplex consensus sequences (DCSs) to correct the variation introduced in the process of library construction and sequencing during data analysis. Unavoidable self-connection of joints, low efficiency of library construction

The second method is called SIP-HAVA-seq. Based on the Duplex Sequencing method, 10 kinds of UIDs are synthesized to form hairpin joints by annealing. Although this method reduces the self-connection of the joints, it greatly reduces the types of UIDs. Not conducive to data correction

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