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Yingbi Li

Publications and source records attributed to Yingbi Li.

10 recordsLinked to original sources
PubMed2006

Analysis of 15 STR loci in Chinese population from Sichuan in West China.

Allele frequencies for 15 STR loci found in PowerPlex 16 System kit were determined in a sample of 200 unrelated individuals living in Sichuan area in west China. The values of observed heterozygosity (Ho), power of discrimination (PD), probability of paternity exclusion (PE) and polymorphism information content (PIC) were calculated. All loci were in accordance with Hardy-Weinberg equilibrium (p<0.05). The obtained frequency distributions were compared with other previously reported population data.

China↗
PubMed2006

A novel diagnostic strategy for trisomy 21 using short tandem repeats.

Molecular technique with STRs can rapidly diagnose aneuploidy. In order to improve its fidelity, we developed a novel STR-based strategy for fast diagnosis of trisomy 21 and constructed a multimarker diagnostic system according to it. The system is based on nine STRs, of which two were previously known and seven were newly identified from the genomic sequence of the long arm of chromosome 21. They were confirmed to be highly polymorphic in the Chinese population by PCR amplification and gel electrophoresis. The combination of nine STR markers, when applied to DNA from 102 Chinese individuals with normal karyotype, did not yield any false-positives, and clearly revealed three different alleles in DNA from 15 out of 18 trisomy 21 patients. The results show that our new strategy can provide an alternative molecular technique for the rapid detection of aneuploidy.

Alleles↗
PubMed2005

[Genetic polymorphisms of fifteen short tandem repeat loci in Chengdu Han population].

OBJECTIVE: To acquire the population genetic data of fifteen short tandem repeat (STR) loci in Chengdu Han population. METHODS: A total of 210 EDTA-blood specimens were collected from the unrelated individuals in Chengdu Han population. The DNA samples were extracted with Chelex method and amplified by multiplex PCR technique. The PCR products were analyzed by an automatic genetic analyzer; the relative fragment's lengths of PCR products were calculated by gene scan analysis software and afterward genotyped by genotype software. RESULTS: Fifteen STR loci of the 210 samples showed a successful result of genotyping. The heterozygosities of the fifteen STR loci in Chengdu Han population were found to be 0.529-0.881; the combined exclusion probability and discrimination power for the fifteen STR loci in Chengdu Han population were determined to be 0.999998 and 7.3 x 10 (-17); respectively. CONCLUSION: The distinct genotype of fifteen STR loci and the sex of sample could be unveiled just through PCR and electrophoresis once, and a higher measured value could be obtained for both the combined discrimination power and the exclusion probability; the fifteen STR loci can meet the needs of the parentage testing and personal identification in forensic medicine.

Asian People↗
PubMed2002

[The relationship between physical distance and genetic distance on chromosome 22].

OBJECTIVE: To construct a genetic map based on data from the Chinese population in northern part of China and to compare relationship between physical distance and genetic distance on chromosome 22. METHODS: PCR amplification was employed to genotype 6 STR loci on chromosome 22, and pedigree analysis was performed. RESULTS: A genetic map of Chinese Han population in the northern part of China was constructed and a preliminary comparison of the physical and genetic distances between 6 STR loci on chromosome 22 was made. CONCLUSION: There is complex relationship between genetic distance and physical distance: the distance between STR loci is related to physical distance but also recombination fraction, and there are differences of the genetic and physical distances on chromosome 22 between Chinese and Caucasian, and between the male and female.

China↗
PubMed2002

[A study of forensic DNA databases].

OBJECTIVE: The forensic DNA databases are very important for individual identification. In order to evaluate the genetic markers used for a forensic DNA databases and the compatibility between the manual DNA typing system and the automatic DNA typing system, a testing DNA database should be constructed. Also, constructing a testing DNA database can increase our understanding of the issue for forensic DNA databases. METHODS: A total of 1000 specimens, including samples of blood, blood stains, salvia stains, semen stains, mixture stains and muscle tissues, were collected from the public security bureau of Chengdu. The DNA of each specimen was extracted by Chelex method and analyzed using Amp-FLP technique. A total of 8 STR loci, including D3S1358, D9S1118, vWA, D5S818, D16S539, D8S1179, CSF1PO and D20S161 were chosen and employed for DNA typing. Each STR locus was amplified by the polymerase chain reaction PCR and the PCR products were typed with the polyacryamide gel electrophoresis. Typing DNA was carried out by comparing with a human allele ladder. A total of 8 human allele ladders for D3S1358, D9S1118, vWA, D5S818, D16S539, D8S1179, CSF1PO and D20S161 were made in-house. Managing software of the testing DNA database was designed using Microsoft Access. RESULTS: The results of DNA typing in 1000 specimens showed that the total discrimination power of 8 STR loci was over 0.99999999. CONCLUSION: This study show that a forensic DNA database should be useful for search purpose. The total discrimination power over 0.99999999 imply that in principle there is no identical genotype at whole 8 STR loci between two persons from a population with 10000000 individuals. This means that 8 STR loci used in this study are suitable to construct forensic DNA databases in Chengdu of China. The result of DNA typing can be repeated and the data have compatibility between the manual DNA typing system and the automatic DNA typing system. The data search in our testing DNA database can be carried out using only some loci of the set of 8 STR markers. Also, the volume of our testing DNA databases could be enlarged easily. The implication from this study is that the legislation should not be negligent before establishing a forensic DNA database. This DNA database provides a model for establishing the forensic DNA databases in China.

Adolescent↗