A competitive real-time fluorescent PCR SNP probe for detection of human genome

Abstract

The invention discloses a competitive real-time fluorescent PCR SNP probe for detecting a human genome, and relates to mononucleotide polymorphic probes. The competitive real-time fluorescent PCR SNP probe for detecting the human genome is provided with a secondary structure. The competitive real-time fluorescent PCR SNP probe comprises a hydrolytic semi-ring-shaped structure of a complete non-complementary sequence and a fluorescent probe body of a complete complementary sequence, SNP is located at a 5' end of the fluorescent probe body, 3-5 basic groups are designed at a 3' end of the fluorescent probe body, so that the 3-5 basic groups are combined with the 5' end of the fluorescent probe body, and therefore the secondary structure is formed. In addition, 3-7 basic groups are added near the 3' end, wherein the 3-7 basic groups and the probe body are not complementary. According to the special structure of the competitive real-time fluorescent PCR SNP probe for detecting the human genome, the hydrolization can be greatly improved, a fluorescent background signal is reduced, so that the sensitivity of a real-time PCR is improved, the specificity of the probe is improved, and the false positive rate is reduced. The sensitivity and the specificity of human genome SNP detection are greatly improved, the false positive rate is reduced, and meanwhile the competitive real-time fluorescent PCR SNP probe is economical, simple and convenient.

Description

technical field [0001] The invention relates to a single nucleotide polymorphism (Single Nucleotide Polymorphism, SNP) probe, in particular to a competitive real-time fluorescent PCR SNP probe for detecting human genome. Background technique [0002] SNP (Single Nucleotide Polymorphism, SNP) mainly refers to the DNA sequence polymorphism caused by the variation of a single nucleotide at the genome level. It is the most common type of heritable variation in humans, accounting for more than 90% of all known polymorphisms. SNPs exist widely in the human genome, with an average of 1 in every 500-1000 base pairs, and it is estimated that the total number can reach 3 million or more. [0003] The polymorphism shown by SNP only involves the variation of a single base, which can be caused by the transition or transversion of a single base, or by the insertion or deletion of a base. But the so-called SNP does not include the latter two situations. [0004] Theoretically speaking, ...

AI Technical Summary

Problems solved by technology

Main disadvantages: low sensitivity, especially in the detection of somatic mutations in tumor tissue, when the target gene mutation ratio in the tissue is less than 20%, false negative results may occur; there are special requirements for reagents and instruments, and it is not easy to popularize; operation Complex, relatively high cost, slow speed, low throughput

Main disadvantages: There are special requirements for reagents and instruments, and it is not easy to popularize; the detection sensitivity is limited, and it is prone to false negatives for low-abundance somatic mutations (<3%) in tumor tissues; the sequencing length is only more than 10 bases, and cannot be detected Analysis of long fragments

The disadvantages of this method are: the new genetic variation in the nucleic acid to be tested cannot be ruled out; the change of DNA melting temperature due to a single base mutation is very small, and this method has high requirements for the sensitivity and resolution of the instrument

But the shortcomings are also obvious, mainly because the throughput is too low, the workload is heavy when a large number of typing is performed, and it is only suitable for partial SNP typing

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