Kit for quickly detecting number of human chromosomes 21 by multiplex real-time fluorescence quantitative PCR (polymerase chain reaction) technique

Abstract

The invention discloses a kit for quickly detecting the number of human chromosomes 21 by a multiplex real-time fluorescence quantitative PCR (polymerase chain reaction) technique, which comprises amplification detection reagents, the amplification detection reagents comprise a pair of primers capable of simultaneously amplifying a certain specific repetitive sequence on the chromosome 21 and a specific repetitive sequence on the chromosome 6, two fluorescent probes for respectively detecting the amplification quantities of the specific repetitive sequences of the chromosomes 21 and 6, a pair of primers capable of simultaneously amplifying another specific repetitive sequence on the chromosome 21 and a specific repetitive sequence on the chromosome 11, and two fluorescent probes for respectively detecting the amplification quantities of the specific repetitive sequences of the chromosomes 21 and 11. The kit can determine the detection result according to Delta CT21-6 value of the chromosomes 21 and 6 and the Delta CT21-11 value of the chromosomes 21 and 11; and the two Delta CT values can be used for independently detecting the number of the chromosomes 21, and the result is more reliable.

Description

technical field [0001] The invention relates to a kit for rapidly detecting the number of human chromosome 21 by multiple real-time fluorescent quantitative PCR technology, which belongs to the field of molecular biology. Background technique [0002] Down syndrome (Down's syndrome), also known as trisomy 21, is the most common aneuploidy disease caused by abnormal chromosome number in humans, and the incidence rate of newborns is 1 / 600-1 / 800. The main manifestations of the children are severe congenital mental retardation and congenital malformations of various organs, and most patients cannot take care of themselves. At present, there is no effective treatment for this disease. Therefore, prenatal diagnosis to prevent the birth of children is the main method to prevent the occurrence of such diseases. For a long time, amniotic fluid cell culture and chromosomal karyotype analysis have become the classic methods of prenatal diagnosis (Caspersson T, Zech L, Johansson C, et ...

AI Technical Summary

Problems solved by technology

However, due to the use of two pairs of primers to amplify different fragments, very small changes in annealing temperature or differences in DNA quality will cause false negative or false positive results, resulting in inaccurate results (Helmy SM, Ismail S, Bassiouni R, et al.Sensitivity of DCSR3 / GAPDH ratio using quantitative real-time PCR in the rapid prenatal diagnosis for down syndrome[J].Fetal Diagn Ther,2009,25(2):220-223.)

[0005] The invention patents with the publication numbers CN100338227A and CN102086469A all disclose the method of detecting the number of chromosome 21 by designing different primers and probes for the specific sequences of different chromosomes. Changes in DNA quality or differences in DNA quality, which can cause false negative or false positive results

On the other hand, there is only one detection site in the above methods, and when a gene mutation occurs in the genome complementary sequence of the primer, it may also cause false negative or false positive experimental results.

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