Detection method and detection system for chromosome multiple abnormality

Abstract

The invention belongs to the technical field of medical chromosome abnormality information detection, and discloses a detection method and detection system for chromosome multiple abnormality. After pre-processing of sample data, the reads value of each chromosome of a sample is obtained, the sample is tested by using t-test, and the expected value and standard deviation of a statistic Ratio undernull hypothesis are estimated; after the expected value and the standard deviation are obtained, a Ratio value is calculated; after the Ratio value is calculated, for different types of chromosomes,different z values are calculated by using different reference groups; after the different z values are calculated, sex chromosomes are detected by using a decision tree classification algorithm. According to the detection method and detection system for chromosome multiple abnormality, the reference groups are selected according to detection objects respectively; a large number of preprocessing methods such as deduplication are performed on data in the early stage, and by using the decision tree algorithm and a random forest algorithm, the detection results are more accurate.

Description

technical field [0001] The invention belongs to the technical field of medical chromosome abnormality information detection, and in particular relates to a detection method and a detection system for chromosome multiple abnormality. Background technique [0002] Before the 1990s, the main method for detecting Down's syndrome was invasive means, such as umbilical cordocentesis, which is to collect fetal blood through maternal abdominal wall puncture under the guidance of ultrasound to obtain fetal information. The advantage of invasive screening is that it is easy and quick to operate. The disadvantage is that the false positive is high, and there may be complications such as hemorrhage, fetal bradycardia, fetal death, infection, early placental separation, fetal blood entering the maternal circulation, and the probability of complications is about 1%. . [0003] After the 1990s, the most common detection methods relied on serological screening and B-ultrasound examination,...

AI Technical Summary

Problems solved by technology

[0011] (1) In the existing chromosome detection technology, the abnormal information of chromosome monosomy or polysome cannot be accurately detected;

[0012] Existing technology also has the problem of inaccurate sex chromosome detection

[0013] (2) Some polyploid detection methods rely too much on the alignment results of completely consistent sequences, and information that cannot be located is considered invalid information

[0014] (3) Some polyploid detection methods only detect specific target chromosomes, and do not include the detection of sex chromosome abnormalities, and the detection range is too small

[0017] Because the test is carried out by collecting samples from pregnant women, it is inevitable that the sample contains the gene sequence of the mother, and the gene sequence of the mother accounts for more than 80% of the total sample, the noise will be very large, and it is difficult to extract effective information

[0018] The human gene sequence is composed of ATCG bases, it is difficult to distinguish the difference between the genes of the mother and the baby, so the noise is difficult to remove, which can only be detected in the noise

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