SNP composite detection system and detection method

Abstract

The invention provides a single nucleotide polymorphism (SNP) composite detection system and an SNP composite detection method. The SNP composite detection system comprises a group of 48 SNP loci suitable for forensic medicine application, an amplification primer group, a mini-sequencing primer group and a universal chip, and can be used for individual identification, ABO genotyping and sex determination. The invention also provides the SNP composite detection method for the individual identification, the ABO genotyping and the sex determination by using the SNP composite detection system. By amplifying nucleotide fragments containing the 48 SNP loci of deoxyribonucleic acid (DNA) of a sample to be detected, performing extension reaction on mini-sequencing primers and performing SNP locus-based genotyping on an amplification product by using the universal chip, the capacity of analyzing trace degraded sample DNA is improved, the sample range of a crime scene is expanded, and powerful technical support is provided for the criminal enforcement and administrative enforcement of public security organs.

Description

technical field [0001] The present invention relates to an individual detection system and method based on genotyping, in particular to a SNP composite detection system and detection method for SNP site typing. Background technique [0002] With the continuous improvement of the scientific, objectivity and accuracy requirements of judicial litigation activities, the field of physical evidence identification continues to develop, requiring more accurate analysis methods to determine the individual source of inspection materials in cases, DNA analysis Because of its accurate test results, it has become an important technical means in the field of physical evidence identification. [0003] At present, forensic DNA laboratories often use the composite PCR-STR typing technology to type the samples of unknown individual origin based on STR loci to achieve the purpose of determining the individual source of the samples. The composite PCR-STR typing technology can detect The DNA fr...

AI Technical Summary

Problems solved by technology

[0003] At present, forensic DNA laboratories often use the compound PCR-STR typing technology to carry out typing based on the STR locus of the specimens of unknown individual origin to achieve the purpose of determining the individual source of the specimens. The compound PCR-STR typing technology can detect DNA fragments are mainly distributed between 300-400bp, but in actual cases, samples that are degraded by various factors (including high temperature, humidity, exposure to sunlight, microorganisms, etc.) are often encountered. The main performance is that the DNA molecules in the samples Damage, fragment breakage, loss, and smaller molecules, etc. When using the composite PCR-STR typing technology to detect these samples, "dominant amplification" or "ineffective amplification" often occurs, resulting in STR genes with larger fragments The seat cannot be effectively classified

Although the amplification efficiency of degraded specimens has been improved to a certain extent by improving the DNA extraction method, increasing the concentration and purity of template DNA, and optimizing PCR amplification conditions, it is still not possible to obtain good typing results for determining the individual source of the specimens. It is difficult to meet the needs of case analysis

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