ABSTRACT
Three SNaPshot multiplex assays were developed to test 23 coding region single nucleotide polymorphisms (SNPs) and one control region SNP outside hypervariable regions (HVR)I and II, which was aimed at increasing the discrimination power of the mitochondrial DNA (mtDNA) typing in forensic casework, and confirming haplogroup assignments of mtDNA profiles in both human population studies and medical research. The selected SNPs targeted the East Asian phylogeny. These multiplex assays were validated by comparing with the sequencing analysis of samples chosen randomly. The mtDNA variations of 100 unrelated individuals from the Wuhan population in China were examined and classified into 31 haplotypes, and the haplotype diversity was estimated to be 0.952. The multiplex SNaPshot method is rapid and robust, and suitable for large-scale screening studies of mtDNA variability.
ABSTRACT
Objective To study the Application of X-linked differentially methylated polymorphism site in forensic medicine.Methods X-STR HUMARA was chosen as a model locus.PCR procedures were performed after digestion using methylation-sensitive restriction endonucleases.STR polymorphism of HUMARA was analyzed and compared in samples collected from male and female individuals.Result After digestion with methylation-sensitive restriction enzyme HpaⅡ,no PCR products were obtained from male samples,whereas PCR products from the female samples were normally typed.In monoclonal tumor cell samples from females,only one allele was detected.Conclusion The differentially methylated X-STR HUMARA locus is a novel marker for mixture analysis of mixed stains,sex determination and discrimination of tumor tissues.
ABSTRACT
Objective To study the primer design for Penta D and Penta E genotyping and investigate the genetic polymorphisms of these two loci in Chinese Han population in Wuhan.Methods 281 unrelated Chinese individuals living in Wuhan were typed by hot-start PCR with re-designed Penta D and Penta E genotyping primers and PAGE technique,and the results were compared with those by the PowerPlex TM 16 system of Promega.Results The amplified fragment size of Penta D and Penta E loci with re-designed primers ranged between 153～198bp and 107～212bp respectively,which were consistent with the results obtained by the re-designed primers and PowerPlex TM 16 system,and the re-designed primers had a higher sensitivity than PowerPlex TM 16 system (0.2ng vs 0.5ng) by silver staining.10 and 21 alleles were observed for Penta D and Penta E in Chinese Han population in Wuhan,and the genotype distributions of the two loci were in accordance with Hardy-Weinberg equilibrium.Family studies confirmed Mendelian inheritance of alleles.The power of discrimination (DP) for Penta D and Penta E were 0.926 2 and 0.986 0,and the power of exclusion (PE) were 0.665 1 and 0.832 5 respectively.Conclusion The re-designed primers for Penta D and Penta E genotyping are reliable.These two loci are highly polymorphic in Chinese Han population and can be used in forensic identification and paternity test.
ABSTRACT
DIA3 typing for human tissues was carried out by IEF- The results showed that the DIA3 typescould be demonstrated in testis, ovary, uterus and dental pulps ;but could not be demonstrated in thehuman brain, liver, kidney, adrenal gland, spleen, intestine, pancrease, heart, lung, skin, muscle, blood,vaginal secretion and hair root. The relative activty of DIA in different human tissues,blood and vagi-nal secretion DIA activity of different tissues and the DIA band intensity by PAGIEF were basecallyconsistent. The author were examined by spectrophotometric analysis. The relative suggests that theDIA3 typing of reproductive organs and teeth by PAGIEF plays a significant role for medicolegal individualization,The vaginal sectetion did not interfere with DIA3 typing of semen in mixed stain for theindividualization.
ABSTRACT
The 87 cases of disputed paternity were analyzed.Among 87 cases,73(83.9~(96))were civil,14(16.1%)criminal.By testing of 12 blood group systems,25 alleged fathers were exclused while 76 alleged fathers were not exclused,in which RCP value were from 9.91% to 99.998% calculafed according to theEssen-M(?)ller theory.In this report the causes of the disputes blood groupsexcluded and the calculation of PI and RCP were discussed.
ABSTRACT
The absorption-elution test using low ionic strength solution (LISS) has been compared with the test using normal saline in MN typing of 258 bloodstain samples stored 1 to 6 years. The accuracy rate was 94.57％ using LISS method. The present study indicated that the LISS method is more sensitive than tests carried out in normal saline.
ABSTRACT
Drowning represents one of the leading causes of unnatural death. The plankton test is still considered as one of the useful methods for medico-legal investigation of death by drowning although controversies concerning the reliability of the test exist. The methods commonly used for detection of planktons generally include microscopic examination after tissue samples are destructed with or without strong acid, and detection of the planktons by molecular biological techniques. The evaluation of the positive results by the former methods are limited by the physical-chemical characters of the planktons. Detection of DNA genetic markers by molecular biological techniques, which can provide abundant information and is applicable to studying various planktons, is a novel method helpful for investigation of drowning. In the present paper, several techniques for detection of planktons were reviewed as references for medico-legal practitioners in investigation of suspected cases of drowning.