Résumé
OBJECTIVES@#To derive general formulas for calculating commonly used kinship index (KI).@*METHODS@#By introducing the Kronecker symbol, the formulas used to calculate the same KI under different genotype combinations were summarized into a unified expression.@*RESULTS@#The general formulas were successfully derived for KI in various case situations, including the paternity index, full sibling index, half sibling index, avuncular index, grandpaternity index, first-cousin index, and second-cousin index between two individuals without or with the mother being involved; grandpaternity index between grandparents and a grandchild without or with the mother being involved; half sibling index between two children with two mothers being involved; full sibling index among three children; and half sibling index among three children with no, one, or two mothers being involved.@*CONCLUSIONS@#The general formulas given in this study simplify the calculation of KIs and facilitate fast and accurate calculation through programming.
Sujets)
Femelle , Enfant , Humains , Paternité , Fratrie , Génotype , Mères , Modèles génétiquesRésumé
X-chromosome short tandem repeats (X-STR) analysis has been confirmed to be effective for kinship testing such as in deficiency paternity cases. The aim of this study was to develop a new multiplex polymerase chain reaction (PCR) system that can simultaneously amplify 9 X-STR loci (GATA172D05, DXS10159, DXS6797, HPRTB, DXS10079, DXS6789, DXS9895, DXS10146 and GATA31E08) in the same PCR reaction, and to obtain the database of the 9 X-STR loci in three ethnic populations in China. The genetic data of 815 (404 females and 411 males) unrelated Han Chinese from Hubei province, and Yi and Zhuang Chinese from Yunnan province were analyzed by using this multiplex system. The results showed that a total of 93 alleles for all these loci were found, and 7 to 20 alleles for each locus were observed. All of the analyzed loci were in agreement with Hardy-Weinberg equilibrium after Bonferroni correction in the three studied populations. The polymorphism information content (PIC) and power of discrimination (PD) in females were 0.6566-0.8531 and 0.8639-0.9684, respectively. Pairwise comparisons of allele frequency distribution showed significant differences in the most of these loci between different populations. The results indicate that this multiplex system is very useful for forensic analysis of different ethnic populations in China.
Sujets)
Humains , Séquence nucléotidique , Chine , Chromosomes X humains , Amorces ADN , Ethnies , Génétique , Répétitions microsatellites , Génétique , Réaction de polymérisation en chaine multiplex , MéthodesRésumé
X-chromosome short tandem repeats (X-STR) analysis has been confirmed to be effective for kinship testing such as in deficiency paternity cases. The aim of this study was to develop a new multiplex polymerase chain reaction (PCR) system that can simultaneously amplify 9 X-STR loci (GATA172D05, DXS10159, DXS6797, HPRTB, DXS10079, DXS6789, DXS9895, DXS10146 and GATA31E08) in the same PCR reaction, and to obtain the database of the 9 X-STR loci in three ethnic populations in China. The genetic data of 815 (404 females and 411 males) unrelated Han Chinese from Hubei province, and Yi and Zhuang Chinese from Yunnan province were analyzed by using this multiplex system. The results showed that a total of 93 alleles for all these loci were found, and 7 to 20 alleles for each locus were observed. All of the analyzed loci were in agreement with Hardy-Weinberg equilibrium after Bonferroni correction in the three studied populations. The polymorphism information content (PIC) and power of discrimination (PD) in females were 0.6566-0.8531 and 0.8639-0.9684, respectively. Pairwise comparisons of allele frequency distribution showed significant differences in the most of these loci between different populations. The results indicate that this multiplex system is very useful for forensic analysis of different ethnic populations in China.
Résumé
Single nucleotide polymorphism (SNP) refers to the single base sequence variation in specific location of the human genome. Phenotype informative SNP has gradually become one of the research hot spots in forensic science. In this paper, the forensic research situation and application prospect of phenotype informative SNP in the characteristics of hair, eye and skin color, height, and facial feature are reviewed.
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Humains , Couleur des yeux/génétique , Génétique légale/tendances , Sciences légales , Génome humain , Poils , Phénotype , Polymorphisme de nucléotide simple/génétiqueRésumé
OBJECTIVE@#To establish a simple, fast and economical technique for multiplex-typing SNPs and to explore its potential forensic application.@*METHODS@#Five Y-SNP loci (IMS-JST164520, IMS-JST021354, IMS-JST003305, M119 and M134) were selected and the allele specific primers of each locus were designed with the universal reporter primers tailed at their 5' end. Alleles of these loci were amplified first by allele specific primers, then amplified by universal reporter primers tagged by fluorescent dye.@*RESULTS@#A fluorescent-multiplex PCR system of the five Y-SNP loci was established. The typing results showed that two different colors of product peaks denoted two different alleles of a SNP locus, and the fragment sizes of alleles among different SNP loci were different. The haplotype diversity of these five loci was estimated to be 0.8655 in Wuhan Han population.@*CONCLUSION@#The multiplex-typing SNPs based on the universal reporter primers is a simple, fast, and economical technique, and may have good application value in forensic medicine.
Sujets)
Femelle , Humains , Mâle , Allèles , Asiatiques/génétique , Chine/ethnologie , Chromosomes Y humains/génétique , Amorces ADN , Génétique légale , Fréquence d'allèle , Marqueurs génétiques , Génétique des populations , Haplotypes , Techniques d'amplification d'acides nucléiques/méthodes , Polymorphisme de nucléotide simple/génétiqueRésumé
OBJECTIVE@#To establish a simple and effective technique for detecting haplotype and heteroplasmy of mtDNA, and investigate their frequencies in Chinese Han population.@*METHODS@#The fragments from 29-290 nt of mtDNA HV II from peripheral leukocytes of 200 unrelated Wuhan Han individuals were analyzed by using PCR-DGGE technique.@*RESULTS@#Seventeen haplotypes were found in the range of 29-290 nt, and the haplotype diversity (HD) was 0.8844. The heterogeneity was observed from 4 individuals, and its frequency was 2%.@*CONCLUSION@#PCR-DGGE is a simple, sensitive and effective technique in analyzing polymorphism and heteroplasmy of mtDNA, and can be used in forensic practice.
Sujets)
Humains , Asiatiques/génétique , Chine/ethnologie , ADN mitochondrial/génétique , Électrophorèse sur gel de polyacrylamide/méthodes , Hétérogénéité génétique , Génétique des populations , Haplotypes , Mutation , Réaction de polymérisation en chaîne/méthodes , Analyse de séquence d'ADNRésumé
OBJECTIVE@#To study the application of PCR-SSCP in forensic mtDNA typing.@*METHODS@#Primers flanking the mtDNA HV-I and HV-II regions were designed. By PCR-SSCP techniques, 70 family trios and 140 unrelated Wuhan Han individuals were investigated and analyzed.@*RESULTS@#In 70 family trios, the SSCP profiles in region HV-I and HV-II of children were not same to that of their fathers in 98.57% and 97.13% respectively but were identical with their mothers. In 140 unrelated Wuhan Han individuals, 21 haplotypes were found in HVI, GD = 0.9556; 16 haplotypes were found in HVII, GD = 0.9356.@*CONCLUSION@#PCR-SSCP technique may be useful in forensic mtDNA typing, especially for screening the suspects.
Sujets)
Humains , Profilage d'ADN/méthodes , Amorces ADN , ADN mitochondrial/génétique , Génétique légale/méthodes , Haplotypes , Pedigree , Réaction de polymérisation en chaîne/méthodes , Polymorphisme de conformation simple brin , Analyse de séquence d'ADNRésumé
OBJECTIVE@#To establish a fluorescent multiplex PCR system for typing Y-STR loci Y-GATA-A7.1, DYS456 and DYS443, and investigate their haplotype frequencies in Chinese Han population.@*METHODS@#203 unrelated males of Han population living in Zhengzhou were typed by fluorescent multiplex amplification system and ABI 3100 genetic analyzer.@*RESULTS@#In Zhengzhou Han population, 5,6 and 6 different alleles were observed for Y-GATA-A7.1, DYS456 and DYS443 loci, and their gene diversity (GD) were 0.669 2, 0.583 9 and 0.705 3 respectively. A total of 44 different haplotypes formed by these three loci was identified and the haplotype diversity (HD) reached 0.952 3.@*CONCLUSION@#The fluorescent multiplex system for these three Y-STR loci will be very powerful for forensic individual identification and paternity testing in Chinese Han population.
Sujets)
Humains , Mâle , Allèles , Chine/ethnologie , Chromosomes Y humains/génétique , Profilage d'ADN , Amorces ADN , Fluorescence , Fréquence d'allèle , Marqueurs génétiques , Génétique des populations , Haplotypes , Réaction de polymérisation en chaîne/méthodes , Séquences répétées en tandemRésumé
<p><b>OBJECTIVE</b>To establish a novel method for the multiplex analysis of the methylation and single nucleotide polymorphism (SNP).</p><p><b>METHODS</b>The imprinted SNP rs220028 was chosen as a model. Genomic DNA, after being digested with methylation sensitive restriction enzyme, were typed by mutagenically separated PCR (MS-PCR). The polymorphism of restriction site was excluded by PCR-RFLP.</p><p><b>RESULTS</b>By post-digestion MS-PCR, the methylated allele was detected selectively, the maternal origin of which was confirmed by pedigree analysis; A=0.5085, G=0.4915,PIC=0.3749.</p><p><b>CONCLUSION</b>The multiplex analysis of methylation markers and SNP can be achieved by post-digestion MS-PCR. The imprinted SNP locus rs220028 is a potentially useful marker in screening Prader-Willi/Angelman syndrome.</p>
Sujets)
Humains , Méthylation de l'ADN , DNA restriction enzymes , Métabolisme , Marqueurs génétiques , Génétique , Réaction de polymérisation en chaîne , Méthodes , Polymorphisme de nucléotide simpleRésumé
OBJECTIVE@#To establish a new method for single nucleotide polymorphism (SNP) typing based on allele specific PCR: fragment length discrepant allele specific PCR (FLDAS-PCR), and study the influence on specific extension by introducing a mismatch at the third or fourth 3'-terminal base of allele specific primers.@*METHODS@#For SNP loci rs759117 and rs760887, two allele specific forward primers, with different length and a mismatch introduced at the third or fourth 3'-terminal base, and a public reverse primer were designed for SNP typing. The genotyping of SNP was determined by the two allele specific fragments different in size after polyacrylamide gel and silver staining.@*RESULTS@#The different homozygote genotypes comprised a single band with different size respectively, and the heterozygote genotypes comprised two bands. Typing results were completely consistent with those by direct sequencing. Non-specific primer extension was decreased remarkably after introducing a mismatch at the third or fourth 3'-terminal base of allele specific primers, and the stringency of PCR reaction was cut down.@*CONCLUSION@#FLDAS-PCR is a simple, rapid and efficient new method for SNP typing. During FLDAS-PCR, specific primers with a mismatch at the third or fourth 3'-terminal base have more power to identify two alleles.
Sujets)
Humains , Allèles , Mésappariement de bases/génétique , ADN/génétique , Amorces ADN , Électrophorèse sur gel de polyacrylamide , Génotype , Réaction de polymérisation en chaîne , Polymorphisme de restriction , Polymorphisme de nucléotide simple , Sensibilité et spécificité , Analyse de séquence d'ADN/méthodesRésumé
This article review the application of chi-square test of various data handling methods and exact test in Hardy-Weinberg equilibrium testing of human genetic marker in population genetics. The importance of HWE-exact test in multiallelic system was emphasized, especially in the study of forensic VNTR and STR typing.
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Humains , Allèles , Loi du khi-deux , Médecine légale , Fréquence d'allèle , Génétique des populations/méthodes , Génotype , Fonctions de vraisemblance , Modèles génétiques , Modèles statistiquesRésumé
OBJECTIVE@#Study on the pattern of changes of bFGF and FGFR1 immunoreactivity occurred in the experimental brain injury model for the purpose of providing the scientific basis for molecular pathological diagnosis, forensic identification, clinical treatment as well as further ascertaining the molecular mechanism of brain injury.@*METHODS@#Male SD rats were divided into normal control, sham operation control and injury groups. The rats of injury groups were subjected to moderate lateral fluid percussion brain injury (0.2 mPa). The injury groups were then subdivided into 30 min, 1, 3, 6, 12 h, 1, 3, 7 d groups according to the time elapsed after injury. The SP immunohistochemistry method was used to examine the expression of both bFGF and FGFR1 factors in rat brain.@*RESULTS@#In the brain of normal control and sham operation control groups, the low expression levels of bFGF and FGFR1 were observed. The increase of bFGF and FGFR1 immunoreactivity could be observed 6 h after injury in cortex and brain stem, reached to the peak at 1 d and remained at the high level up to 3 d, then partly declined at 7 d. In hippocampus, however, the increase occur as early as 3 h after injury, reached to the peak at 1 d and then decreased progressively, and returned to basal level at 7 d.@*CONCLUSION@#The results suggested that brain injury induced the gene expressions of bFGF and FGFR1. The bFGF may contribute to maintenance of nerve cell survival and the repair of damaged neural tissues after CNS injury and the patterns of their level change were quite regular and can be used for timing of injury in forensic medicine aspect.
Sujets)
Animaux , Mâle , Rats , Encéphale/métabolisme , Lésions encéphaliques/anatomopathologie , Modèles animaux de maladie humaine , Facteur de croissance fibroblastique de type 2/métabolisme , Hippocampe/métabolisme , Immunohistochimie , Rat Sprague-Dawley , Récepteur FGFR1/métabolismeRésumé
OBJECTIVE@#Studying the genetic polymorphism of X-STR locus DXS9898 in Han population.@*METHODS@#296 unrelated Chinese individuals (199 females and 97 males) living in Chengdu were investigated using PCR and PAG electrophoresis followed by silver staining.@*RESULTS@#6 alleles were observed and the range of fragment size was 189-214 bp. The genotype distribution of DXS9898 locus was in accordance with Hardy-Weinberg equilibrium. Family survey confirmed Mendelian inheritance of alleles. The observed heterozygosity in females was 0.5930, the discriminating power (Dp) were 0.5667 and 0.9420 for males and females respectively. The power of exclusion were 0.5862 and 0.4392 for trio and duo respectively.@*CONCLUSION@#The results demonstrated that the locus is highly polymorphic and can be used in forensic identification and parentage testing.
Sujets)
Femelle , Humains , Mâle , Allèles , Asiatiques/génétique , Chine , Médecine légale , Fréquence d'allèle , Génétique des populations , Génotype , Réaction de polymérisation en chaîne , Polymorphisme génétique , Séquences répétées en tandemRésumé
Single nucleotide polymorphisms (SNPs) is a new genetic marker system following RFLP and microsatellite polymorphism. It has been shown to have the characteristics of high-density, inheritance stability and facilitation in analysis automation. SNPs can be detected by electrophoresis, endonuclease-cleavage, PCR and sequencing, and can be used extensively in gene mapping, disease-correlativity analysis, population genetics and drug research.