Fluorescent detecting method for X chromosome STR gene site typing

Abstract

The invention discloses a fluorescent detecting method for X chromosome STR gene site typing, which comprises the following steps: allele typing standard substance preparation: carrying out RCP amplification by respectively taking plasmids in different gene types, which comprise an X chromosome STR gene site DXS7132, an X chromosome STR gene site DXS6799 and an X chromosome STR gene site DXS6804 as a template and taking a primer pair of which the 5' ends are marked with fluorescent molecules as primers, and mixing fragments of all alleles in the equal ratio according to molecular weight so as to obtain an allele typing standard substance; carrying out RCP amplification on three X chromosome STR alleles contained in an X chromosome to be detected in the same amplification system; and carrying out capillary electrophoresis separation on the allele typing standard substance with a fluorescent molecule mark obtained by the RCP amplification and the STR allele fragments of the X chromosome to be detected so as to perform standard typing in fluorescent detection typing. The invention is applied to paternity test, individual recognition, sex identification, X linkage inheritance virulent gene positioning and susceptibility gene detection.

Description

technical field [0001] The invention belongs to the field of biotechnology, and relates to a detection method for chromosome typing, in particular to a fluorescence detection method for X chromosome STR gene locus typing. Background technique [0002] Short tandem repeats (short tandem repeats, referred to as STR) is a type of microsatellite DNA sequence formed by tandem repeats with 2-7 base pairs as the core unit; STR forms the STR gene locus due to the change in the number of core repeat units genetic polymorphisms. In the human genome, there is an STR gene locus every 6-10kb on average, which provides a rich source of high-information gene loci for forensic personal identification and paternity testing. [0003] The typing of STR alleles has the following significant advantages in research and practical application: good repeatability, stable and reliable typing results, simple and fast operation; the fragment length is generally 100-400bp, easy to be amplified by PCR a...

AI Technical Summary

Problems solved by technology

[0007] 1) Difficulties encountered when using such kits to increase genetic markers;

[0008] 2) These X-STR loci were developed based on data from groups other than the Chinese population (mainly the white population). Some of these loci have poor gene frequency distribution in the Chinese population and low personal recognition ability

[0009] 3) Foreign commercial kits are expensive

However, the STR classification disclosed in this invention is silver staining, and the silver staining detection has low requirements on the cost of experimental equipment, and the test operation is simple and easy to master. However, there are many manual operations in the experiment, and the workload is heavy, and the experimental results are affected by the proficiency of the personnel.

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